# 1978 United States Senate elections

The 1978 United States Senate elections were held on November 7, in the middle of Democratic President Jimmy Carter's term. The 33 seats of Class 2 were contested in regular elections. Special elections were also held to fill vacancies.
Thirteen seats changed hands between parties, resulting in a net gain of three seats for the Republicans allowing them to break the Democrats' filibuster-proof majority. Democrats nevertheless retained a 58–41 majority.

## Results summary

| 58 | 1 | 41 |
| Democratic | I | Republican |
| Parties | Parties | | | | | Total |
| Parties | Parties | Democratic | Republican | Independent | Other | Total |
| Last elections (1976) Before these elections | Last elections (1976) Before these elections | 61 | 38 | 1 | 0 | 100 |
| Not up | Not up | 43 | 21 | 1 | 0 | 65 |
| Up | Up | 18 | 17 | 0 | — | 35 |
| | Class 2 (1972→1978) | 16 | 17 | — | — | 33 |
| | Special: Class 1 | 1 | — | — | — | 1 |
| | Special: Class 3 | 1 | — | — | — | 1 |
| Incumbent retired | Incumbent retired | 5 | 5 | — | — | 10 |
| | Held by same party | 2 | 3 | — | — | 5 |
| | Replaced by other party | 2 Republicans replaced by 2 Democrats 3 Democrats replaced by 3 Republicans | 2 Republicans replaced by 2 Democrats 3 Democrats replaced by 3 Republicans | — | — | 5 |
| | Result | 4 | 6 | — | — | 10 |
| Incumbent ran | Incumbent ran | 13 | 12 | — | — | 25 |
| | Won re-election | 6 | 9 | — | — | 15 |
| | Lost re-election | 2 Republicans replaced by 2 Democrats 5 Democrats replaced by 5 Republicans | 2 Republicans replaced by 2 Democrats 5 Democrats replaced by 5 Republicans | — | — | 7 |
| | Lost renomination, but held by same party | 2 | 0 | — | — | 2 |
| | Lost renomination, and party lost | 1 Republican replaced by 1 Democrat | 1 Republican replaced by 1 Democrat | — | — | 1 |
| | Result | 11 | 14 | 0 | 0 | 25 |
| Total elected | Total elected | 15 | 20 | 0 | 0 | 35 |
| Net gain/loss | Net gain/loss | 3 | 3 | | | 3 |
| Nationwide vote | Nationwide vote | 15,302,929 | 14,794,225 | 299,624 | 278,078 | 30,674,856 |
| | Share | 49.89% | 48.23% | 0.98% | 0.91% | 100% |
| Result | Result | 58 | 41 | 1 | 0 | 100 |
Source: Clerk of the United States House of Representatives

## Gains, losses, and holds
### Retirements

Five Republicans and three Democrats retired instead of seeking re-election. One Democrat retired instead of seeking election to finish the unexpired term and one Democrat retired instead of seeking election to a full term.
| State | Senator | Replaced by |
| Alabama (regular) | John Sparkman | Howell Heflin |
| Arkansas | Kaneaster Hodges Jr. | David Pryor |
| Kansas | James B. Pearson | Nancy Kassebaum |
| Minnesota (special) | Muriel Humphrey | David Durenberger |
| Mississippi | James Eastland | Thad Cochran |
| Nebraska | Carl Curtis | J. James Exon |
| Oklahoma | Dewey F. Bartlett | David Boren |
| South Dakota | James Abourezk | Larry Pressler |
| Virginia | William L. Scott | John Warner |
| Wyoming | Clifford Hansen | Alan Simpson |

### Defeats

Three Republicans and four Democrats sought re-election but lost in the primary or general election. One Democrat sought election to a full term but lost in the general election, one Democrat sought election to a full term but lost in the primary and one Democrat sought election to finish the unexpired term but lost in the primary.
| State | Senator | Replaced by |
| Alabama (special) | Maryon Pittman Allen | Donald Stewart |
| Colorado | Floyd Haskell | William L. Armstrong |
| Iowa | Dick Clark | Roger Jepsen |
| Maine | William Hathaway | William Cohen |
| Massachusetts | Edward Brooke | Paul Tsongas |
| Michigan | Robert P. Griffin | Carl Levin |
| Minnesota (regular) | Wendell R. Anderson | Rudy Boschwitz |
| Montana | Paul G. Hatfield | Max Baucus |
| New Hampshire | Thomas J. McIntyre | Gordon J. Humphrey |
| New Jersey | Clifford P. Case | Bill Bradley |

### Post-election changes

One Democrat resigned on May 7, 1980, and was later replaced by Democratic appointee.
| State | Senator | Replaced by |
| Maine (Class 1) | Edmund Muskie | George J. Mitchell |

## Change in composition
### Before the elections

| D$_1$ | D$_2$ | D$_3$ | D$_4$ | D$_5$ | D$_6$ | D$_7$ | D$_8$ | D$_9$ | D$_{10}$ |
| D$_{20}$ | D$_{19}$ | D$_{18}$ | D$_{17}$ | D$_{16}$ | D$_{15}$ | D$_{14}$ | D$_{13}$ | D$_{12}$ | D$_{11}$ |
| D$_{21}$ | D$_{22}$ | D$_{23}$ | D$_{24}$ | D$_{25}$ | D$_{26}$ | D$_{27}$ | D$_{28}$ | D$_{29}$ | D$_{30}$ |
| D$_{40}$ | D$_{39}$ | D$_{38}$ | D$_{37}$ | D$_{36}$ | D$_{35}$ | D$_{34}$ | D$_{33}$ | D$_{32}$ | D$_{31}$ |
| D$_{41}$ | D$_{42}$ | D$_{43}$ | D$_{44}$ Ala. (reg) Ran | D$_{45}$ Ala. (sp) Ran | D$_{46}$ Ark. Retired | D$_{47}$ Colo. Ran | D$_{48}$ Del. Ran | D$_{49}$ Ga. Ran | D$_{50}$ Iowa Ran |
| Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | D$_{51}$ Ky. Ran |
| D$_{60}$ S.D. Retired | D$_{59}$ R.I. Ran | D$_{58}$ N.H. Ran | D$_{57}$ Mont. Ran | D$_{56}$ Miss. Retired | D$_{55}$ Minn. (sp) Retired | D$_{54}$ Minn. (reg) Ran | D$_{53}$ Maine Ran | D$_{52}$ La. Ran | D$_{51}$ Ky. Ran |
| D$_{61}$ W.Va. Ran | I$_1$ | R$_{38}$ Wyo. Retired | R$_{37}$ Va. Retired | R$_{36}$ Texas Ran | R$_{35}$ Tenn. Ran | R$_{34}$ S.C. Ran | R$_{33}$ Ore. Ran | R$_{32}$ Okla. Retired | R$_{31}$ N.C. Ran |
| R$_{21}$ | R$_{22}$ Alaska Ran | R$_{23}$ Idaho Ran | R$_{24}$ Ill. Ran | R$_{25}$ Kan. Retired | R$_{26}$ Mass. Ran | R$_{27}$ Mich. Ran | R$_{28}$ Neb. Retired | R$_{29}$ N.J. Ran | R$_{30}$ N.M. Ran |
| R$_{20}$ | R$_{19}$ | R$_{18}$ | R$_{17}$ | R$_{16}$ | R$_{15}$ | R$_{14}$ | R$_{13}$ | R$_{12}$ | R$_{11}$ |
| R$_1$ | R$_2$ | R$_3$ | R$_4$ | R$_5$ | R$_6$ | R$_7$ | R$_8$ | R$_9$ | R$_{10}$ |

### After the elections

| D$_1$ | D$_2$ | D$_3$ | D$_4$ | D$_5$ | D$_6$ | D$_7$ | D$_8$ | D$_9$ | D$_{10}$ |
| D$_{20}$ | D$_{19}$ | D$_{18}$ | D$_{17}$ | D$_{16}$ | D$_{15}$ | D$_{14}$ | D$_{13}$ | D$_{12}$ | D$_{11}$ |
| D$_{21}$ | D$_{22}$ | D$_{23}$ | D$_{24}$ | D$_{25}$ | D$_{26}$ | D$_{27}$ | D$_{28}$ | D$_{29}$ | D$_{30}$ |
| D$_{40}$ | D$_{39}$ | D$_{38}$ | D$_{37}$ | D$_{36}$ | D$_{35}$ | D$_{34}$ | D$_{33}$ | D$_{32}$ | D$_{31}$ |
| D$_{41}$ | D$_{42}$ | D$_{43}$ | D$_{44}$ Ala. (reg) Re-elected | D$_{45}$ Ala. (sp) Hold | D$_{46}$ Ark. Hold | D$_{47}$ Del. Re-elected | D$_{48}$ Ga. Re-elected | D$_{49}$ Ky. Re-elected | D$_{50}$ La. Re-elected |
| Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | Majority → | D$_{51}$ Mont. Hold |
| R$_{41}$ S.D. Gain | I$_1$ | D$_{58}$ Okla. Gain | D$_{57}$ N.J. Gain | D$_{56}$ Neb. Gain | D$_{55}$ Mich. Gain | D$_{54}$ Mass. Gain | D$_{53}$ W.Va. Re-elected | D$_{52}$ R.I. Re-elected | D$_{51}$ Mont. Hold |
| R$_{40}$ N.H. Gain | R$_{39}$ Miss. Gain | R$_{38}$ Minn. (sp) Gain | R$_{37}$ Minn. (reg) Gain | R$_{36}$ Maine Gain | R$_{35}$ Iowa Gain | R$_{34}$ Colo. Gain | R$_{33}$ Wyo. Hold | R$_{32}$ Va. Hold | R$_{31}$ Texas Re-elected |
| R$_{21}$ | R$_{22}$ Alaska Re-elected | R$_{23}$ Idaho Re-elected | R$_{24}$ Ill. Re-elected | R$_{25}$ Kan. Hold | R$_{26}$ N.M. Re-elected | R$_{27}$ N.C. Re-elected | R$_{28}$ Ore. Re-elected | R$_{29}$ S.C. Re-elected | R$_{30}$ Tenn. Re-elected |
| R$_{20}$ | R$_{19}$ | R$_{18}$ | R$_{17}$ | R$_{16}$ | R$_{15}$ | R$_{14}$ | R$_{13}$ | R$_{12}$ | R$_{11}$ |
| R$_1$ | R$_2$ | R$_3$ | R$_4$ | R$_5$ | R$_6$ | R$_7$ | R$_8$ | R$_9$ | R$_{10}$ |
| Key | D$_#$ Democratic R$_#$ Republican I$_#$ Independent |

## Race summary
### Special elections during the 95th Congress

In these special elections, the winner was seated during 1978 or before January 3, 1979; ordered by election date, then state.
| State | Incumbent | Incumbent | Incumbent | Result | Candidates |
| State | Senator | Party | Electoral history | Result | Candidates |
| Alabama (Class 3) | Maryon Pittman Allen | Democratic | 1978 (appointed) | Interim appointee lost nomination. Democratic hold. | ▌Y Donald Stewart (Democratic) 55.1% ▌James D. Martin (Republican) 43.3% Others ▌Michael R. A. Erdey (Libertarian) 0.8% ▌A. J. Killingsworth (Prohibition) 0.8% |
| Minnesota (Class 1) | Muriel Humphrey | DFL | 1978 (appointed) | Interim appointee retired. Republican gain. | ▌Y David Durenberger (Republican) 61.4% ▌Bob Short (DFL) 34.6% ▌Paul Helm (American) 2.9% Others ▌Christine Frank (Socialist) 0.7% ▌Frederick Hewitt (Libertarian) 0.3% |

### Elections leading to the next Congress

In these general elections, the winners were elected for the term beginning January 3, 1979; ordered by state.
All of the elections involved the Class 2 seats.
| State | Incumbent | Incumbent | Incumbent | Result | Candidates |
| State | Senator | Party | Electoral history | Result | Candidates |
| Alabama | John Sparkman | Democratic | 1946 (special) 1948 1954 1960 1966 1972 | Incumbent retired. Democratic hold. | ▌Y Howell Heflin (Democratic) 94.0% ▌Jerome B. Couch (Prohibition) 6.0% |
| Alaska | Ted Stevens | Republican | 1968 (appointed) 1970 1972 | Incumbent re-elected. | ▌Y Ted Stevens (Republican) 75.6% ▌Donald W. Hobbs (Democratic) 24.1% |
| Arkansas | Kaneaster Hodges Jr. | Democratic | 1977 (appointed) | Interim appointee retired. Democratic hold. | ▌Y David Pryor (Democratic) 76.5% ▌Tom Kelly (Republican) 16.3% ▌John J. Black (Independent) 7.2% |
| Colorado | Floyd Haskell | Democratic | 1972 | Incumbent lost re-election. Republican gain. | ▌Y William L. Armstrong (Republican) 58.7% ▌Floyd Haskell (Democratic) 40.3% Others ▌Vedder V. Dorn (United States Party) 0.7% ▌John Shue (National Statesman) 0.3% |
| Delaware | Joe Biden | Democratic | 1972 | Incumbent re-elected. | ▌Y Joe Biden (Democratic) 58.0% ▌James H. Baxter (Republican) 41.0% ▌Donald G. Gies (American) 1.0% |
| Georgia | Sam Nunn | Democratic | 1972 (special) 1972 | Incumbent re-elected. | ▌Y Sam Nunn (Democratic) 83.1% ▌John W. Stokes (Republican) 16.9% |
| Idaho | James A. McClure | Republican | 1972 | Incumbent re-elected. | ▌Y James A. McClure (Republican) 68.4% ▌Dwight Jensen (Democratic) 31.6% |
| Illinois | Charles H. Percy | Republican | 1966 1972 | Incumbent re-elected. | ▌Y Charles H. Percy (Republican) 53.3% ▌Alex Seith (Democratic) 45.5% Others ▌William R. Roy (Libertarian) 0.5% ▌Patricia Grogan (Socialist Workers) 0.5% ▌Gerald Rose (Socialist Labor) 0.2% |
| Iowa | Dick Clark | Democratic | 1972 | Incumbent lost re-election. Republican gain. | ▌Y Roger Jepsen (Republican) 51.1% ▌Dick Clark (Democratic) 47.9% Others ▌Gerald Leo Baker (Independent) 0.5% ▌Ben L. Olson (Libertarian) 0.4% |
| Kansas | James B. Pearson | Republican | 1962 (appointed) 1962 (special) 1966 1972 | Incumbent retired. Republican hold. Incumbent resigned December 23, 1978 to give successor preferential seniority. Successor appointed December 23, 1978. | ▌Y Nancy Kassebaum (Republican) 53.9% ▌William R. Roy (Democratic) 42.4% ▌James R. Maher (Conservative) 3.0% ▌Russell Mikels (Prohibition) 0.7% |
| Kentucky | Walter Dee Huddleston | Democratic | 1972 | Incumbent re-elected. | ▌Y Walter Dee Huddleston (Democratic) 61.0% ▌Louie R. Guenthner Jr. (Republican) 36.9% ▌Anthony A. McCord (American) 2.1% |
| Louisiana | J. Bennett Johnston | Democratic | 1972 (appointed) 1972 | Incumbent re-elected. | ▌Y J. Bennett Johnston (Democratic) 59.4% ▌Woody Jenkins (Democratic) 40.6% |
| Maine | William Hathaway | Democratic | 1972 | Incumbent lost re-election. Republican gain. | ▌Y William Cohen (Republican) 56.6% ▌William Hathaway (Democratic) 33.9% ▌Hayes E. Gahagan (Independent) 7.4% Others ▌John J. Jannace (Independent) 1.5% ▌Plato Truman (Independent) 0.6% |
| Massachusetts | Edward Brooke | Republican | 1966 1972 | Incumbent lost re-election. Democratic gain. | ▌Y Paul Tsongas (Democratic) 55.1% ▌Edward Brooke (Republican) 44.9% |
| Michigan | Robert P. Griffin | Republican | 1966 (appointed) 1966 1972 | Incumbent lost re-election. Democratic gain. | ▌Y Carl Levin (Democratic) 52.1% ▌Robert P. Griffin (Republican) 47.9% |
| Minnesota | Wendell R. Anderson | DFL | 1976 (appointed) | Interim appointee lost election. Republican gain. Incumbent resigned December 29, 1978 to give successor preferential seniority. Successor appointed December 30, 1978. | ▌Y Rudy Boschwitz (Republican) 56.6% ▌Wendell R. Anderson (DFL) 40.4% Others ▌Sal Carlone (American) 1.5% ▌William Peterson (Socialist Workers) 0.6% ▌Brian Coyle (Public Interest Independent) 0.5% ▌Jean T. Brust (Workers) 0.2% ▌Leonard Richards (Libertarian) 0.2% |
| Mississippi | James Eastland | Democratic | 1942 1948 1954 1960 1966 1972 | Incumbent retired. Republican gain. Incumbent resigned December 27, 1978 to give successor preferential seniority. Successor appointed December 27, 1978. | ▌Y Thad Cochran (Republican) 45.3% ▌Maurice Dantin (Democratic) 31.8% ▌Charles Evers (Independent) 22.6% ▌Henry Kirksey (Independent) 0.3% |
| Montana | Paul G. Hatfield | Democratic | 1978 (appointed) | Interim appointee lost nomination. Democratic hold. Incumbent resigned December 12, 1978 to give successor preferential seniority. Successor appointed December 15, 1978. | ▌Y Max Baucus (Democratic) 55.7% ▌Larry Williams (Republican) 44.3% |
| Nebraska | Carl Curtis | Republican | 1954 1960 1966 1972 | Incumbent retired. Democratic gain. | ▌Y J. James Exon (Democratic) 67.6% ▌Donald Shasteen (Republican) 32.3% |
| New Hampshire | Thomas J. McIntyre | Democratic | 1962 (special) 1966 1972 | Incumbent lost re-election. Republican gain. | ▌Y Gordon J. Humphrey (Republican) 50.7% ▌Thomas J. McIntyre (Democratic) 48.5% ▌Craig Franklin (Libertarian) 0.8% |
| New Jersey | Clifford P. Case | Republican | 1954 1960 1966 1972 | Incumbent lost renomination. Democratic gain. | ▌Y Bill Bradley (Democratic) 55.3% ▌Jeffrey Bell (Republican) 43.1% Others ▌Herbert Harry Shaw (Independent) 0.2% ▌Bill Gahres (Independent) 0.2% ▌Jack Moyers (Independent) 0.2% ▌Robert Bowen (Labor) 0.2% ▌J.M. Carter Jr. (Independent) 0.2% ▌Jasper C. Gould (Independent) 0.2% ▌William R. Thorn (Independent) 0.1% ▌Paul Ferguson (Independent) 0.1% ▌Alice Conner (Independent) 0.1% |
| New Mexico | Pete Domenici | Republican | 1972 | Incumbent re-elected. | ▌Y Pete Domenici (Republican) 53.4% ▌Toney Anaya (Democratic) 46.6% |
| North Carolina | Jesse Helms | Republican | 1972 | Incumbent re-elected. | ▌Y Jesse Helms (Republican) 54.5% ▌John Ingram (Democratic) 45.5% |
| Oklahoma | Dewey F. Bartlett | Republican | 1972 | Incumbent retired. Democratic gain. | ▌Y David Boren (Democratic) 65.5% ▌Robert B. Kamm (Republican) 32.9% Others ▌Glenn E. Hager (Independent) 0.5% ▌Riley Donica (Independent) 0.4% ▌Paul Edward Trent (Independent) 0.4% ▌Richard King Carter (Independent) 0.3% |
| Oregon | Mark Hatfield | Republican | 1966 1972 | Incumbent re-elected. | ▌Y Mark Hatfield (Republican) 61.6% ▌Vernon Cook (Democratic) 38.3% |
| Rhode Island | Claiborne Pell | Democratic | 1960 1966 1972 | Incumbent re-elected. | ▌Y Claiborne Pell (Democratic) 75.1% ▌James G. Reynolds (Republican) 24.9% |
| South Carolina | Strom Thurmond | Republican | 1954 (write-in) 1954 (appointed) 1956 (resigned) 1956 (special) 1960 1966 1972 | Incumbent re-elected. | ▌Y Strom Thurmond (Republican) 55.6% ▌Charles D. Ravenel (Democratic) 44.4% |
| South Dakota | James Abourezk | Democratic | 1972 | Incumbent retired. New senator elected. Republican gain. | ▌Y Larry Pressler (Republican) 66.8% ▌Don Barnett (Democratic) 33.2% |
| Tennessee | Howard Baker | Republican | 1966 1972 | Incumbent re-elected. | ▌Y Howard Baker (Republican) 55.5% ▌Jane Eskind (Democratic) 40.3% ▌Thomas Anderson (Independent) 4.0% ▌Fern Lucius Keasler (Independent) 0.2% |
| Texas | John Tower | Republican | 1961 (special) 1966 1972 | Incumbent re-elected. | ▌Y John Tower (Republican) 49.8% ▌Bob Krueger (Democratic) 49.3% Others ▌Luis A. Diaz de Leon (Raza Unida) 0.8% ▌Miguel Pendas (Socialist Workers) 0.2% |
| Virginia | William L. Scott | Republican | 1972 | Incumbent retired. Republican hold. Incumbent resigned January 1, 1979 to give successor preferential seniority. Successor appointed January 2, 1979. | ▌Y John Warner (Republican) 50.2% ▌Andrew P. Miller (Democratic) 49.8% |
| West Virginia | Jennings Randolph | Democratic | 1958 (special) 1960 1966 1972 | Incumbent re-elected. | ▌Y Jennings Randolph (Democratic) 50.5% ▌Arch A. Moore Jr. (Republican) 49.5% |
| Wyoming | Clifford Hansen | Republican | 1966 1972 | Incumbent retired. Republican hold. Incumbent resigned December 31, 1978 to give successor preferential seniority. Successor appointed January 1, 1979. | ▌Y Alan Simpson (Republican) 62.2% ▌Raymond B. Whitaker (Democratic) 37.8% |

## Closest races

Nine races had a margin of victory under 10%:
| State | Party of winner | Margin |
| Virginia | Republican | 0.38% |
| Texas | Republican | 0.53% |
| West Virginia | Democratic | 0.96% |
| New Hampshire | Republican (flip) | 2.20% |
| Iowa | Republican (flip) | 3.21% |
| Michigan | Democratic (flip) | 4.29% |
| New Mexico | Republican | 6.82% |
| Illinois | Republican | 7.87% |
| North Carolina | Republican | 9.02% |
Oklahoma was the tipping point state with a margin of 32.6%.

## Alabama

There were two elections in Alabama, due to the death of senator Jim Allen.

### Alabama (regular)

Democrat John Sparkman retired and was succeeded by Howell Heflin, the former chief justice of the Supreme Court of Alabama. Heflin, the Democratic candidate, faced no Republican opponent in the general election, defeating Prohibition Party nominee Jerome B. Couch.
General election :
| Party | Party | Candidate | Votes | % |
| | Democratic | Howell Heflin | 547,054 | 93.99% |
| | Prohibition | Jerome B. Couch | 34,951 | 6.01% |
| Majority | Majority | Majority | 512,103 | 87.98% |
| Turnout | Turnout | Turnout | 582,005 | |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

### Alabama (special)

Following the death of senator Jim Allen, his widow Maryon was appointed by governor George Wallace to fill the vacancy until a special election could be held. In this election, Democratic state senator Donald W. Stewart defeated former Republican congressman James D. Martin to serve the remaining two years of the term.
General election :
| Party | Party | Candidate | Votes | % |
| | Democratic | Donald W. Stewart | 401,852 | 54.93% |
| | Republican | James D. Martin | 316,170 | 43.22% |
| | Libertarian | Michael R. A. Erdey | 6,006 | 0.82% |
| | Prohibition | A. J. Killingsworth | 5,814 | 0.80% |
| | Peace and Freedom | Joseph T. Robino | 1,768 | 0.24% |
| Majority | Majority | Majority | 85,682 | 11.74% |
| Turnout | Turnout | Turnout | 731,610 | |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## Alaska

Republican Ted Stevens won reelection to a second full (his third total) term, defeating Democrat Donald Hobbs.
1978 United States Senate election in Alaska :
| Party | Party | Candidate | Votes | % |
| | Republican | Ted Stevens (Incumbent) | 92,783 | 75.59% |
| | Democratic | Donald Hobbs | 29,574 | 24.09% |
| | Write-ins | Write-ins | 384 | 0.31% |
| Majority | Majority | Majority | 63,209 | 51.50% |
| Turnout | Turnout | Turnout | 122,741 | |
| | Republican hold | Republican hold | Swing | |

## Arkansas

Following the death of senator John L. McClellan, then Kaneaster Hodges Jr. was appointed by governor David Pryor to fill the vacancy until a special election could be held. In this election, Democratic state governor David Pryor defeated former Republican challenger Thomas Kelly Jr. to serve the six-year term.
1978 United States Senate election in Arkansas :
| Party | Party | Candidate | Votes | % |
| | Democratic | David Pryor | 395,506 | 76.48% |
| | Republican | Tom Kelly | 84,308 | 16.30% |
| | Independent | John G. Black | 37,211 | 7.20% |
| | None | Write-ins | 113 | 0.02% |
| Majority | Majority | Majority | 311,198 | 60.18% |
| Turnout | Turnout | Turnout | 517,138 | |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## Colorado

Democrat Floyd Haskell decided to run for re-election to a second term, but was defeated by William L. Armstrong, the Republican nominee and the U.S. Representative.
1978 United States Senate election in Colorado :
| Party | Party | Candidate | Votes | % |
| | Republican | William L. Armstrong | 480,801 | 58.69% |
| | Democratic | Floyd Haskell (Incumbent) | 330,148 | 40.30% |
| | United States Party | Vedder V. Dorn | 5,789 | 0.71% |
| | National Statesman | John Shue | 2,518 | 0.31% |
| Majority | Majority | Majority | 150,653 | 18.39% |
| Turnout | Turnout | Turnout | 819,256 | |
| | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic |

## Delaware

Democratic United States senator Joe Biden won re-election to a second term, defeating Republican challenger James H. Baxter Jr., the Delaware Secretary of Agriculture.
General election :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Joe Biden (Incumbent) | 93,930 | 57.96% | +7.48% |
| | Republican | James H. Baxter Jr. | 66,479 | 41.02% | −8.08% |
| | American | Donald G. Gies | 1,663 | 1.02% | +0.68% |
| Majority | Majority | Majority | 27,451 | 16.94% | +15.56% |
| Turnout | Turnout | Turnout | 162,072 | | |
| | Democratic hold | Democratic hold | Swing | | |

## Georgia

Democrat Sam Nunn won re-election to a second term.
General election :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Sam Nunn (incumbent) | 536,320 | 83.13% | +29.17% |
| | Republican | John W. Stokes | 108,808 | 16.87% | −29.14% |
| Majority | Majority | Majority | 427,512 | 66.27% | +58.32% |
| Turnout | Turnout | Turnout | 645,128 | | |
| | Democratic hold | Democratic hold | Swing | | |

## Idaho

Republican James A. McClure was elected to a second term in office.
1978 United States Senate election in Idaho :
| Party | Party | Candidate | Votes | % |
| | Republican | James A. McClure (Incumbent) | 194,412 | 68.44% |
| | Democratic | Dwight Jensen | 89,635 | 31.56% |
| Majority | Majority | Majority | 104,777 | 36.88% |
| Turnout | Turnout | Turnout | 284,047 | |
| | Republican hold | Republican hold | Swing | |

## Illinois

Republican Charles H. Percy ran for re-election to a third term in the United States Senate. Percy was opposed by Democratic nominee Alex Seith (D), attorney and former member of the Cook County Zoning Board of Appeals. Though Percy had been expected to coast to re-election over Seith, a first-time candidate, the election quickly became competitive. In the last few days of the campaign, a desperate Percy ran a television advertisement that featured him apologizing and acknowledging that, "I got your message and you're right." Percy's last-ditch effort appeared to have paid off, as he was able to edge out Seith to win what would end up being his third and final term in the Senate.
1978 United States Senate election in Illinois :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Charles H. Percy (Incumbent) | 1,698,711 | 53.34% | −8.88% |
| | Democratic | Alex Seith | 1,448,187 | 45.47% | +8.13% |
| | Libertarian | Bruce Lee Green | 16,320 | 0.51% | |
| | Socialist Workers | Patricia Grogan | 15,922 | 0.50% | |
| | Socialist Labor | Gerald Rose | 5,465 | 0.18% | |
| | Write-ins | | 159 | 0.00% | |
| Majority | Majority | Majority | 250,524 | 7.87% | −17.00% |
| Turnout | Turnout | Turnout | 3,184,764 | | |
| | Republican hold | Republican hold | Swing | | |

## Iowa

Democrat Dick Clark decided to run for re-election to a second term, but was defeated by Roger Jepsen, the Republican nominee and former Lieutenant Governor of Iowa.
1978 United States Senate election in Iowa :
| Party | Party | Candidate | Votes | % |
| | Republican | Roger Jepsen | 421,598 | 51.13% |
| | Democratic | Dick Clark (Incumbent) | 395,066 | 47.91% |
| | Independent | Gerald Leo Baker | 4,223 | 0.51% |
| | Libertarian | Ben L. Olson | 3,689 | 0.45% |
| Majority | Majority | Majority | 26,532 | 3.22% |
| Turnout | Turnout | Turnout | 824,576 | |
| | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic |

## Kansas

Republican James B. Pearson retired and was succeeded by Nancy Kassebaum, the daughter of Alf Landon, defeating Democratic nominee William R. Roy, the former U.S. Representative. Roy also lost to Bob Dole in the 1974 election for Kansas' other Senate seat.
1978 United States Senate election in Kansas :
| Party | Party | Candidate | Votes | % |
| | Republican | Nancy Kassebaum | 403,354 | 53.86% |
| | Democratic | William R. Roy | 317,602 | 42.41% |
| | Conservative | James R. Maher | 22,497 | 3.00% |
| | Prohibition | Russell Mikels | 5,386 | 0.72% |
| Majority | Majority | Majority | 85,752 | 11.45% |
| Turnout | Turnout | Turnout | 748,839 | |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## Kentucky

Democrat Walter Huddleston was re-elected to a second term.
General election :
| Party | Party | Candidate | Votes | % |
| | Democratic | Walter Huddleston (Incumbent) | 290,730 | 60.98% |
| | Republican | Louie R. Guenthner Jr. | 175,766 | 36.86% |
| | American | Anthony Albert McCord | 10,244 | 2.15% |
| | None | Write-Ins | 32 | 0.01% |
| Majority | Majority | Majority | 114,964 | 24.12 |
| Turnout | Turnout | Turnout | 476,783 | |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## Louisiana

Democrat J. Bennett Johnston won re-election to unopposed and his second term.
1978 United States Senate election in Louisiana :
| Party | Party | Candidate | Votes | % |
| | Democratic | J. Bennett Johnston (Incumbent) | Unopposed | |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## Maine

Democrat William Hathaway decided to run for re-election to a second term, but was defeated by William Cohen, the Republican nominee and the United States Congressman from Maine's 2nd congressional district and Hayes Gahagan, former Maine State Senator
1978 United States Senate election in Maine :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | William Cohen | 212,294 | 56.59% | +9.83% |
| | Democratic | William Hathaway (Incumbent) | 127,327 | 33.94% | −19.29% |
| | Independent | Hayes E. Gahagan | 27,824 | 7.42% | |
| | Independent | John J. Jannace | 5,553 | 1.48% | |
| | Independent | Plato Truman | 2,116 | 0.56% | |
| Majority | Majority | Majority | 84,967 | 22.65% | +16.19% |
| Turnout | Turnout | Turnout | 375,114 | | |
| | Republican gain from Democratic | Republican gain from Democratic | Swing | | |

## Massachusetts

Republican Edward Brooke was defeated by Democratic congressman Paul E. Tsongas.
Republican primary :
| Party | Candidate | Votes | % |
| Republican | Edward Brooke (Incumbent) | 146,351 | 53.25% |
| Republican | Avi Nelson | 128,388 | 46.72% |
| | All others | 78 | 0.03% |
Democratic primary :
| Party | Candidate | Votes | % |
| Democratic | Paul Tsongas | 296,915 | 35.55% |
| Democratic | Paul Guzzi | 258,960 | 31.01% |
| Democratic | Kathleen Sullivan Alioto | 161,036 | 19.28% |
| Democratic | Howard Phillips | 65,397 | 7.83% |
| Democratic | Elaine Noble | 52,464 | 6.28% |
| | All others | 379 | 0.05% |
General election :
| Party | Party | Candidate | Votes | % |
| | Democratic | Paul E. Tsongas | 1,093,283 | 55.06% |
| | Republican | Edward Brooke (Incumbent) | 890,584 | 44.85% |
| | | All others | 1,833 | 0.09% |
| Total votes | Total votes | Total votes | 1,985,700 | 68.01% |
| Majority | Majority | Majority | 202,699 | 10.21% |
| | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican |

## Michigan

Republican Robert P. Griffin ran for re-election to a third term, but was defeated by the Democratic candidate, and former Detroit City Council President Carl Levin.
General election :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Carl Levin | 1,484,193 | 52.1% | N/A |
| | Republican | Robert P. Griffin (Incumbent) | 1,362,165 | 47.8% | −4.29% |
| | Independent | Others | 272 | 0.01% | −52.13% |
| Majority | Majority | Majority | 122,028 | 4.29% | |
| Turnout | Turnout | Turnout | 2,846,630 | | |
| | Democratic gain from Republican | Democratic gain from Republican | Swing | | |

## Minnesota

There were two elections in Minnesota, due to the death of Hubert Humphrey.

### Minnesota (regular)

Democrat Wendell Anderson was defeated by Republican challenger businessman Rudy Boschwitz.
In 1978, all three key statewide races in Minnesota were up for election—the Governorship, and both Senate Seats (the other Senate seat belonged to Hubert Humphrey, who died in 1978). But, there was a particular oddity to the three races—all three had incumbents who were never elected to the office in the first place. This became a well played issue by the Republicans—a billboard put up across the state read, "The DFL is going to face something scary -- an election".
When Walter Mondale resigned after being elected to the Vice Presidency in 1976, sitting Governor Wendell Anderson resigned in order to be appointed by his successor Rudy Perpich to the open seat. This act did not sit well with the electorate. Plywood magnate Rudy Boschwitz campaigned as a liberal Republican and spent freely of his own money, but all that seemed to really matter was that he was neither a DFLer or Wendell Anderson in an election cycle where both were rejected by the voters. The result was not even close—the challenger Boschwitz won in a 16-point landslide as all three statewide offices switched into Republican hands.
Democratic primary election :
| Party | Candidate | Votes | % |
| Democratic (DFL) | Wendell Anderson (Incumbent) | 286,209 | 56.9% |
| Democratic (DFL) | John S. Connolly | 159,974 | 31.8% |
| Democratic (DFL) | Daryl W. Anderson | 23,159 | 4.6% |
| Democratic (DFL) | Lloyd M. Roberts | 12,709 | 2.5% |
| Democratic (DFL) | Dick Bullock | 11,485 | 2.3% |
| Democratic (DFL) | Emil L. Moses | 9,580 | 1.9% |
Republican primary election :
| Party | Party | Candidate | Votes | % |
| | Ind.-Republican | Rudy Boschwitz | 185,393 | 86.8% |
| | Ind.-Republican | Harold Stassen | 28,170 | 13.2% |
General election :
| Party | Party | Candidate | Votes | % |
| | Ind.-Republican | Rudy Boschwitz | 894,092 | 56.57% |
| | Democratic (DFL) | Wendell Anderson (Incumbent) | 638,375 | 40.39% |
| | American | Sal Carlone | 23,261 | 1.47% |
| | Socialist Workers | William Peterson | 9,856 | 0.62% |
| | Independent | Brian J. Coyle | 8,083 | 0.51% |
| | Workers League | Jean T. Brust | 3,891 | 0.25% |
| | Libertarian | Leonard J. Richards | 2,992 | 0.19% |
| | Others | Write-ins | 72 | 0.01% |
| Majority | Majority | Majority | 255,717 | 16.18% |
| Turnout | Turnout | Turnout | 1,580,622 | |
| | Ind.-Republican gain from Democratic (DFL) | Ind.-Republican gain from Democratic (DFL) | Ind.-Republican gain from Democratic (DFL) | Ind.-Republican gain from Democratic (DFL) |

### Minnesota (special)

Incumbent Muriel Humphrey retired. Democratic candidate Bob Short was defeated by Republican candidate David Durenberger.
In 1978, all three key statewide races in Minnesota were up for election—the Governorship, and both Senate Seats (the other Senate seat belonged to Wendell Anderson, who, as Governor of Minnesota, appointed himself to fill the seat vacated by Walter Mondale, when Mondale ascended to the Vice Presidency in 1976). But, there was a particular oddity to the three races—all three had incumbents who were never elected to the office in the first place. This became a well played issue by the Republicans: a billboard put up across the state read, "The DFL is going to face something scary — an election".
When Hubert H. Humphrey died in office in January 1978, sitting Governor Rudy Perpich appointed Humphrey's widow, Muriel to sit until a special election could be held later that year. However, Muriel Humphrey opted not to seek election to the seat in her own right, and the DFL nominated former Texas Rangers owner Bob Short to run in the subsequent special election. The Independent-Republicans, on their part, nominated the liberal Republican David Durenberger, creating an unusual race in which the DFL candidate was positioned to the right of the Independent-Republican candidate. In addition to the general sense of dissatisfaction voters felt for the DFL, the DFL also had to contend with a large number of liberal members of the DFL, who were dissatisfied with Short's positions on hot button issues such as abortion, motorboat usage in the Boundary Waters Canoe area, and government spending, crossing party lines to vote for Durenberger. As a result, Durenberger won in a 26.9-percent landslide as the governorship and both U.S. Senate seats switched into Republican hands.
Democratic special primary election :
| Party | Candidate | Votes | % |
| Democratic (DFL) | Bob Short | 257,289 | 48.0% |
| Democratic (DFL) | Donald M. Fraser | 253,818 | 47.4% |
| Democratic (DFL) | Sharon Anderson | 16,094 | 3.0% |
| Democratic (DFL) | Richard A. Palmer | 8,425 | 1.6% |
Republican special primary election :
| Party | Candidate | Votes | % |
| Ind.-Republican | David Durenberger | 139,187 | 67.3% |
| Ind.-Republican | Malcolm Moos | 32,314 | 15.6% |
| Ind.-Republican | Ken Nordstrom | 14,635 | 7.1% |
| Ind.-Republican | Will Lundquist | 12,261 | 5.9% |
| Ind.-Republican | Adell H. Campbell | 8,523 | 4.1% |
Special election :
| Party | Party | Candidate | Votes | % |
| | Ind.-Republican | David Durenberger | 957,908 | 61.47% |
| | Democratic (DFL) | Bob Short | 538,675 | 34.57% |
| | American | Paul Helm | 45,402 | 2.91% |
| | Socialist Workers | Christine Frank | 11,397 | 0.73% |
| | Libertarian | Frederick Hewitt | 4,116 | 0.26% |
| | Others | Write-ins | 878 | 0.06% |
| Majority | Majority | Majority | 419,233 | 26.90% |
| Turnout | Turnout | Turnout | 1,558,376 | |
| | Ind.-Republican gain from Democratic (DFL) | Ind.-Republican gain from Democratic (DFL) | Ind.-Republican gain from Democratic (DFL) | Ind.-Republican gain from Democratic (DFL) |

## Mississippi

Democrat James Eastland retired. Republican Thad Cochran won the open seat over Democrat Maurice Dantin, former District Attorney and Independent Charles Evers, Mayor of Fayette.
Evers was the first African American elected since the Reconstruction era to be mayor in any Mississippi city in 1969. He ran as an independent, and as a result his campaign divided the Democrats and allowed Cochran to win the senate seat with a 45 percent plurality. This made him the first Republican in a century to win a statewide election in Mississippi for any office except US President. Eastland resigned on December 27, 1978, to give Cochran a seniority advantage over new incoming senators.
Mississippi U.S. Senate Election, 1978 :
| Party | Party | Candidate | Votes | % |
| | Republican | Thad Cochran | 267,302 | 45.3% |
| | Democratic | Maurice Dantin | 187,541 | 31.8% |
| | Independent | Charles Evers | 133,646 | 22.6% |
| | Independent | Henry Jay Kirksey | 1,747 | 0.3% |
| Majority | Majority | Majority | 79,761 | 13.52% |
| Turnout | Turnout | Turnout | 590,236 | |
| | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic |

## Montana

Following the death of senator Lee Metcalf on January 12, 1978, Montana Supreme Court Chief Justice Paul G. Hatfield was appointed to serve for the remainder of Metcalf's term. Hatfield opted to run for a full term in office, but was overwhelmingly defeated in the Democratic primary by Congressman Max Baucus of the 1st congressional district. Baucus advanced to the general election, where he was opposed by Larry R. Williams, an author and the Republican nominee. Baucus ended up defeating Williams by a solid margin to win his first term in the Senate, and, following Hatfield's resignation on December 12, 1978, he began serving his first term in the Senate.
Democratic Party primary :
| Party | Party | Candidate | Votes | % |
| | Democratic | Max Baucus | 87,085 | 65.25% |
| | Democratic | Paul G. Hatfield (Incumbent) | 25,789 | 19.32% |
| | Democratic | John Driscoll | 18,184 | 13.62% |
| | Democratic | Steve Shugrue | 2,404 | 1.80% |
| Total votes | Total votes | Total votes | 133,462 | 100.00% |
Republican Primary :
| Party | Party | Candidate | Votes | % |
| | Republican | Larry R. Williams | 35,479 | 61.66% |
| | Republican | Bill Osborne | 16,436 | 28.57% |
| | Republican | Clancy Rich | 5,622 | 9.77% |
| Total votes | Total votes | Total votes | 57,537 | 100.00% |
1978 United States Senate election in Montana :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Max Baucus | 160,353 | 55.69% | +3.74% |
| | Republican | Larry R. Williams | 127,589 | 44.31% | −3.74% |
| Majority | Majority | Majority | 32,764 | 11.38% | +7.48% |
| Turnout | Turnout | Turnout | 287,942 | | |
| | Democratic hold | Democratic hold | Swing | | |

## Nebraska

Republican Carl Curtis retired instead of seeking a fifth term. In the elections, Democratic nominee J. James Exon won the open seat over Republican Donald Eugene Shasteen.
General election :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | J. James Exon | 334,096 | 67.66% | +20.82% |
| | Republican | Donald Eugene Shasteen | 159,708 | 32.34% | −20.82% |
| Majority | Majority | Majority | 174,390 | 35.32% | +28.99% |
| Turnout | Turnout | Turnout | 493,802 | | |
| | Democratic gain from Republican | Democratic gain from Republican | Swing | | |

## New Hampshire

Incumbent Democrat Thomas J. McIntyre decided to run for re-election to a fourth term, but was defeated by Gordon J. Humphrey, the Republican nominee also a professional pilot and conservative activist.
1978 United States Senate election in New Hampshire :
| Party | Party | Candidate | Votes | % |
| | Republican | Gordon J. Humphrey | 133,745 | 50.71% |
| | Democratic | Thomas J. McIntyre (Incumbent) | 127,945 | 48.51% |
| | Libertarian | Craig Franklin | 2,070 | 0.78% |
| Majority | Majority | Majority | 5,800 | 2.20% |
| Turnout | Turnout | Turnout | 263,760 | |
| | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic |

## New Jersey

Republican Clifford P. Case narrowly lost renomination to anti-tax conservative Jeff Bell, but the Democratic nominee, former professional basketball player Bill Bradley, easily won the general election.
New Jersey Democratic primary :
| Party | Party | Candidate | Votes | % |
| | Democratic | Bill Bradley | 217,502 | 58.90% |
| | Democratic | Richard Leone | 97,667 | 26.45% |
| | Democratic | Alexander J. Menza | 32,386 | 8.77% |
| | Democratic | Kenneth C. McCarthy | 9,524 | 2.58% |
| | Democratic | Wesley K. Bell | 8,800 | 2.38% |
| | Democratic | Ray Rollinson | 3,374 | 0.91% |
| Total votes | Total votes | Total votes | 369,253 | 100.00% |
Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Jeff Bell | 118,555 | 50.74% |
| | Republican | Clifford P. Case (incumbent) | 115,082 | 49.26% |
| Total votes | Total votes | Total votes | 233,637 | 100.00% |
New Jersey general election :
| Party | Party | Candidate | Votes | % |
| | Democratic | Bill Bradley | 1,082,960 | 55.32% |
| | Republican | Jeff Bell | 844,200 | 43.13% |
| | Independent | Herbert H. Shaw | 4,736 | 0.24% |
| | Independent | Bill Gahres | 3,817 | 0.19% |
| | Independent | Jack Moyers | 3,809 | 0.19% |
| | U.S. Labor | Robert Bowen | 3,656 | 0.19% |
| | Independent | J. M. Carter Jr. | 3,618 | 0.18% |
| | Independent | Jasper C. Gould | 2,955 | 0.15% |
| | Independent | William R. Thorn | 2,776 | 0.14% |
| | Independent | Paul Ferguson | 2,604 | 0.13% |
| | Independent | Alice Conner | 2,384 | 0.12% |
| Majority | Majority | Majority | 238,760 | 12.19% |
| Turnout | Turnout | Turnout | 1,957,515 | |
| | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican |

## New Mexico

Republican senator Pete Domenici successfully ran for re-election to a second term, defeating Democrat Toney Anaya, Attorney General of New Mexico.
General election :
| Party | Party | Candidate | Votes | % |
| | Republican | Pete Domenici (Incumbent) | 183,442 | 53.41% |
| | Democratic | Toney Anaya | 160,045 | 46.59% |
| Majority | Majority | Majority | 23,397 | 6.81% |
| Total votes | Total votes | Total votes | 343,487 | 100.00% |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## North Carolina

The general election was fought between the Republican Incumbent Jesse Helms and Democrat John Ingram. Helms won re-election, by a slightly wider margin than in 1972.
1978 North Carolina U.S. Senate Democratic primary election – First round :
| Party | Party | Candidate | Votes | % |
| | Democratic | Luther H. Hodges Jr. | 260,868 | 40.08% |
| | Democratic | John Ingram | 170,715 | 26.23% |
| | Democratic | Lawrence Davis | 105,381 | 16.19% |
| | Democratic | McNeill Smith | 82,703 | 12.71% |
| | Democratic | Dave McKnight | 9,422 | 1.45% |
| | Democratic | William Griffin | 8,907 | 1.37% |
| | Democratic | Tom Sawyer | 8,482 | 1.30% |
| Turnout | Turnout | Turnout | 650,942 | |
1978 North Carolina U.S. Senate Democratic primary election – Second round :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | John Ingram | 244,469 | 54.24% | +28.01% |
| | Democratic | Luther H. Hodges Jr. | 206,223 | 45.76% | +5.68% |
| Turnout | Turnout | Turnout | 450,692 | | |
Jesse Helms won the Republican Party's nomination unopposed.
1978 North Carolina U.S. Senate election :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Jesse Helms (Incumbent) | 619,151 | 54.51% | +0.50% |
| | Democratic | John Ingram | 516,663 | 45.49% | −0.50% |
| Turnout | Turnout | Turnout | 1,135,814 | | |

## Oklahoma

Republican Dewey F. Bartlett retired instead of seeking a second term due to his declining health. In the elections, Democratic nominee David Boren won the open seat over Republican Robert B. Kamm.
1978 United States Senate election in Oklahoma :
| Party | Party | Candidate | Votes | % |
| | Democratic | David Boren | 493,953 | 65.49% |
| | Republican | Robert B. Kamm | 247,857 | 32.86% |
| | Independent | Glenn E. Hager | 3,875 | 0.51% |
| | Independent | Riley Donica | 3,355 | 0.44% |
| | Independent | Paul Edward Trent | 3,015 | 0.40% |
| | Independent | Richard King Carter | 2,209 | 0.29% |
| Majority | Majority | Majority | 246,096 | 32.63% |
| Turnout | Turnout | Turnout | 754,264 | |
| | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican |
Bartlett died 2 months after leaving the U.S. Senate

## Oregon

Republican senator Mark Hatfield successfully ran for re-election to a third term, defeating Democrat Vernon Cook, State Legislator and candidate for U.S. Representative in 1970 and 1974.
1978 United States Senate election in Oregon :
| Party | Party | Candidate | Votes | % |
| | Republican | Mark Hatfield (Incumbent) | 550,165 | 61.64% |
| | Democratic | Vernon Cook | 341,616 | 38.28% |
| | Independent | Write-Ins | 737 | 0.08% |
| Majority | Majority | Majority | 208,549 | 23.36% |
| Turnout | Turnout | Turnout | 892,518 | |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## Rhode Island

Democrat Claiborne Pell successfully sought re-election, defeating Republican James G. Reynolds.
Democratic primary :
| Party | Party | Candidate | Votes | % |
| | Democratic | Claiborne Pell (Incumbent) | 69,729 | 87.01% |
| | Democratic | Raymond J. Greiner | 6,076 | 7.58% |
| | Democratic | Francis P. Kelley | 4,330 | 5.41% |
| Majority | Majority | Majority | 63,653 | 79.43% |
| Total votes | Total votes | Total votes | 80,135 | 100.00% |
General election :
| Party | Party | Candidate | Votes | % |
| | Democratic | Claiborne Pell (Incumbent) | 229,557 | 75.11% |
| | Republican | James G. Reynolds | 76,061 | 24.89% |
| Majority | Majority | Majority | 153,496 | 50.22% |
| Total votes | Total votes | Total votes | 305,618 | 100.00% |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## South Carolina

Popular incumbent Republican Strom Thurmond defeated Democratic challenger Charles D. Ravenel.
The South Carolina Democratic Party held their primary for governor on June 13, 1978. Charles D. Ravenel, an unsuccessful candidate in the 1974 gubernatorial contest, originally planned to run for governor again in 1978, but was convinced by Vice President Walter Mondale in 1977 to run for senator. He garnered over 50% of the vote in the primary and avoided a runoff election.
South Carolina Democratic primary :
| Party | Candidate | Votes | % |
| Democratic | Charles D. Ravenel | 205,348 | 55.9% |
| Democratic | John Bolt Culbertson | 69,184 | 18.9% |
| Democratic | Tom Triplett | 50,957 | 13.9% |
| Democratic | Tom McElveen | 41,550 | 11.3% |
Senator Strom Thurmond faced no opposition from South Carolina Republicans and avoided a primary election.
Thurmond generally ignored Ravenel on the campaign and refused to debate him. When they did cross paths, Thurmond criticized Ravenel for never having held a political office. Ravenel did not help his cause by his actions in the 1974 gubernatorial race when he refused to endorse the Democratic nominee after he had been disqualified. This irritated many Democrats and they also accused him of being nothing more than a liberal New Yorker. Age was beginning to become an issue with Thurmond, so to combat perceptions of old age, Thurmond often appeared with his children on the campaign trail. While 1978 was generally a Democratic year, Thurmond was able to pull off a commanding victory over Ravenel.
South Carolina general election :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Strom Thurmond (Incumbent) | 351,733 | 55.6% | −7.9% |
| | Democratic | Charles D. Ravenel | 281,119 | 44.4% | +7.9% |
| | No party | Write-Ins | 257 | 0.0% | 0.0% |
| Majority | Majority | Majority | 70,614 | 11.2% | −15.8% |
| Turnout | Turnout | Turnout | 633,109 | 57.7% | −7.5% |
| | Republican hold | Republican hold | Swing | | |

## South Dakota

Incumbent Democrat James Abourezk retired instead of seeking a second term. In the elections, Republican congressman Larry Pressler won the open seat over Democratic former mayor of Rapid City Don Barnett, thus becoming the first Vietnam veteran to serve in the Senate
1978 United States Senate election in South Dakota :
| Party | Party | Candidate | Votes | % |
| | Republican | Larry Pressler | 170,832 | 66.84% |
| | Democratic | Don Barnett | 84,767 | 33.16% |
| Majority | Majority | Majority | 86,065 | 33.68% |
| Turnout | Turnout | Turnout | 255,599 | |
| | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic |

## Tennessee

Two-term popular incumbent Howard Baker, who had served as United States Senate Minority Leader since 1977, ran for reelection against first-time candidate and Democratic Party activist Jane Eskind.
In the August 3 Democratic primary Eskind won in an open primary against eight other candidates:
* Eskind - 196,156 (34.52%)
* Bruce - 170,795 (30.06%)
* Lee - 89,939 (15.83%)
* Boyd - 48,458 (8.53%)
* Bradley - 22,130 (3.90%)
* Heinsohn - 17,787 (3.13%)
* Foster - 10,671 (1.88%)
* Nyabongo - 7,682 (1.35%)
* Vick - 4,414 (0.78%)
* Write-in - 147 (0.03%)
In the Republican primary, also held August 3, Baker easily emerged as the winner:
* Baker - 205,680 (83.44%)
* Howard - 21,154 (8.58%)
* Boles - 8,899 (3.61%)
* Patty - 3,941 (1.60%)
* Seiler - 3,831 (1.55%)
* Trapp - 2,994 (1.22%)
Baker won with a 15-point margin in the general election, held on November 7:
General election :
| Party | Party | Candidate | Votes | % |
| | Republican | Howard Baker (Incumbent) | 642,644 | 55.54% |
| | Democratic | Jane Eskind | 466,228 | 40.29% |
| | Independent | Thomas J. Anderson | 45,908 | 3.97% |
| | Independent | Fern L. Keasler | 2,243 | 0.19% |
| | None | Write-Ins | 71 | 0.01% |
| Majority | Majority | Majority | 176,416 | 15.25% |
| Turnout | Turnout | Turnout | 1,157,094 | |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## Texas

Republican incumbent John Tower won re-election to a fourth term over Democrat Bob Krueger, U.S. Congressman of Texas's 21st congressional district.
General election :
| Party | Party | Candidate | Votes | % |
| | Republican | John Tower (Incumbent) | 1,151,376 | 49.8% |
| | Democratic | Bob Krueger | 1,139,149 | 49.3% |
| | Raza Unida | Luis A. Diaz de Leon | 17,869 | 0.8% |
| | Socialist Workers | Miguel Pendas | 4,018 | 0.2% |
| | None | Others | 128 | 0.0% |
| Majority | Majority | Majority | 12,227 | 0.5% |
| Turnout | Turnout | Turnout | 2,312,540 | |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## Virginia

Incumbent William L. Scott retired. Former Secretary of the Navy Republican John Warner beat Attorney General of Virginia Andrew P. Miller. Scott then resigned January 1, 1979 and Warner was appointed January 2, 1979 for early seniority purposes.
1978 United States Senate election in Virginia :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | John Warner | 613,232 | 50.17% | −1.28% |
| | Democratic | Andrew P. Miller | 608,511 | 49.79% | +3.67% |
| | Write-ins | | 513 | 0.04% | +0.04% |
| Majority | Majority | Majority | 4,721 | 0.39% | +0.39% |
| Turnout | Turnout | Turnout | 1,222,256 | | |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## West Virginia

Democratic incumbent Jennings Randolph won re-election to a fifth term over Republican Arch Moore, former governor of West Virginia.
1978 United States Senate election in West Virginia :
| Party | Party | Candidate | Votes | % |
| | Democratic | Jennings Randolph (Incumbent) | 249,034 | 50.48% |
| | Republican | Arch A. Moore Jr. | 244,317 | 49.52% |
| Majority | Majority | Majority | 4,717 | 0.92% |
| Turnout | Turnout | Turnout | 493,351 | |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## Wyoming

Incumbent Republican Clifford Hansen retired instead of seeking a third term. In the elections, Republican nominee Alan K. Simpson won the open seat over Democrat Raymond B. Whitaker, an attorney from Casper and nominee for U.S. Senate in 1960.
1978 United States Senate election in Wyoming :
| Party | Party | Candidate | Votes | % |
| | Republican | Alan Simpson | 82,908 | 62.17% |
| | Democratic | Raymond B. Whitaker | 50,456 | 37.83% |
| Majority | Majority | Majority | 32,452 | 24.34% |
| Turnout | Turnout | Turnout | 133,364 | |
| | Republican hold | Republican hold | Republican hold | Republican hold |