# 2018 United States House of Representatives elections in Arizona

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The 2018 United States House of Representatives elections in Arizona were held on November 6, 2018, to elect the nine U.S. representatives from the State of Arizona, one from each of the state's nine congressional districts. The elections coincided with the 2018 Arizona gubernatorial election, as well as other elections to the U.S. House of Representatives, elections to the United States Senate and various state and local elections. The 2018 general elections saw the Democratic party gain the 2nd congressional district, thus flipping the state from a 5–4 Republican advantage to a 5–4 Democratic advantage, the first time since the 2012 election in which Democrats held more House seats in Arizona than the Republicans.

## Overview
### Statewide

| Party | Party | Candidates | Votes | Votes | Seats | Seats | Seats |
| Party | Party | Candidates | No. | % | No. | +/– | % |
| | Democratic | 9 | 1,179,193 | 50.37 | 5 | 1 | 55.56 |
| | Republican | 9 | 1,139,251 | 48.67 | 4 | 1 | 44.44 |
| | Green | 2 | 22,378 | 0.96 | 0 | | 0.0 |
| | Write-in | 3 | 147 | 0.01 | 0 | | 0.0 |
| Total | Total | 23 | 2,341,270 | 100.0 | 9 | | 100.0 |
Popular vote
Democratic
50.37%
Republican
48.67%
Green
0.96%
Other
0.01% :
House seats
Democratic
55.56%
Republican
44.44% :

### By district

Results of the 2018 United States House of Representatives elections in Arizona by district:
| District | Democratic | Democratic | Republican | Republican | Others | Others | Total | Total | Result |
| District | Votes | % | Votes | % | Votes | % | Votes | % | Result |
| District 1 | 143,240 | 53.83% | 122,784 | 46.14% | 65 | 0.03% | 266,089 | 100.0% | Democratic hold |
| District 2 | 161,000 | 54.73% | 133,083 | 45.24% | 69 | 0.02% | 294,152 | 100.0% | Democratic gain |
| District 3 | 114,650 | 63.87% | 64,868 | 36.13% | 0 | 0.00% | 179,518 | 100.0% | Democratic hold |
| District 4 | 84,521 | 30.51% | 188,842 | 68.16% | 3,672 | 1.33% | 277,035 | 100.0% | Republican hold |
| District 5 | 127,027 | 40.58% | 186,037 | 59.42% | 0 | 0.00% | 313,064 | 100.0% | Republican hold |
| District 6 | 140,559 | 44.81% | 173,140 | 55.19% | 0 | 0.00% | 313,699 | 100.0% | Republican hold |
| District 7 | 113,044 | 85.61% | 301 | 0.20% | 19,007 | 14.39% | 132,051 | 100.0% | Democratic hold |
| District 8 | 135,569 | 44.53% | 168,835 | 55.46% | 13 | 0.01% | 304,417 | 100.0% | Republican hold |
| District 9 | 159,583 | 61.09% | 101,662 | 38.91% | 0 | 0.00% | 261,245 | 100.0% | Democratic hold |
| Total | 1,179,193 | 50.37% | 1,139,251 | 48.66% | 22,826 | 0.97% | 2,341,270 | 100.0% | |

## District 1

The 1st district is home to the Grand Canyon and stretches along the eastern and northeastern portions of the state and includes Casa Grande, Flagstaff, and Marana. This district has a significant Native-American population, making up 25% of the population in the district. This district is home to a number of Indian reservations, including the Gila River Indian Community, Hopi Reservation, and the Navajo Nation. Incumbent Democrat Tom O'Halleran, who had represented the district since 2017, ran for re-election. He was elected with 51% of the vote in 2016, and the district had a PVI of R+2, making it one of the most competitive in the state with a PVI of R+2.

### Democratic primary
#### Candidates
##### Nominee

* Tom O'Halleran, incumbent U.S. Representative

##### Withdrawn

* Miguel Olivas

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Tom O'Halleran (incumbent) | 64,114 | 100.0 |
| Total votes | Total votes | Total votes | 64,114 | 100.0 |

### Republican primary

The district was one of 36 Democratic-held House districts targeted by the National Republican Congressional Committee.

#### Candidates
##### Nominee

* Wendy Rogers, retired air force pilot and perennial candidate

##### Eliminated in primary

* Tiffany Shedd, attorney
* Steve Smith, state senator

##### Declined

* T. J. Shope, state representative

#### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | Wendy Rogers | Tiffany Shedd | Steve Smith | Other | Undecided |
| Grassroots Partners (R-Smith) | July 15–16, 2018 | 393 | ± 4.6% | 23% | 15% | 27% | – | – |
| Data Orbital (R-Defending Rural Arizona PAC) | June 28–30, 2018 | 450 | ± 4.59% | 22% | 15% | 10% | 3% | 50% |

#### Endorsements

U.S. representatives
* Dana Rohrabacher, U.S. representative from California's 48th congressional district (1989–present)
Organizations
* Courageous Conservatives PAC
* Tea Party Nation
U.S. Senators
* Jon Kyl, former U.S. Senator (R-AZ)
U.S. representatives
* Susan Brooks, U.S. representative from Indiana's 5th congressional district (2013–present)
* Mike Conaway, U.S. representative from Texas's 11th congressional district (2005–present)
* Rick Crawford, U.S. representative from Arkansas's 1st congressional district (2011–present)
* Sean Duffy, U.S. representative from Wisconsin's 7th congressional district (2011–present)
* John Faso, U.S. representative from New York's 19th congressional district (2017–present)
* Karen Handel, U.S. representative from Georgia's 6th congressional district (2017–present)
* Martha Roby, U.S. representative from Alabama's 2nd congressional district (2011–present)
* Mike Rogers, U.S. representative from Alabama's 3rd congressional district (2003–present)
* Austin Scott, U.S. representative from Georgia's 8th congressional district (2011–present)
* Elise Stefanik, U.S. representative from New York's 21st congressional district (2015–present)
* Glenn Thompson, U.S. representative from Pennsylvania's 5th congressional district (2009–present)
* Ann Wagner, U.S. representative from Missouri's 2nd congressional district (2013–present)
* Jackie Walorski, U.S. representative from Indiana's 2nd congressional district (2013–present)
State officials
* Michele Reagan, Secretary of State of Arizona
State legislators
* Tim Dunn, state representative
* Roger Hooper, former state representative
* Drew John, state representative
* Bill McGibbon, former state representative
* Steve Pierce, former state Sen. President
Organizations
* Maggie's List
U.S. Senators
* Ted Cruz, U.S. Senator from Texas
U.S. representatives
* Andy Biggs, U.S. representative from Arizona's 5th congressional district (2017–present)
* Trent Franks, U.S. representative from Arizona's 8th congressional district (2003–2017)
* Barry Goldwater Jr., U.S. representative from California's 20th congressional district (1969–1983)
* Jim Jordan, U.S. representative from Ohio's 4th congressional district (2007–present) and House Freedom Caucus Chair
* Debbie Lesko, U.S. representative from Arizona's 8th congressional district (2018–present)
* Mark Meadows, U.S. representative from North Carolina's 11th congressional district (2013–present), and co-founder of the House Freedom Caucus
State officials
* Jeff DeWit, Arizona State Treasurer and Trump Campaign COO
State legislators
* John Allen, house majority leader
* Sylvia Allen, state senator
* Mark Finchem, state representative
* Gail Griffin, senate majority whip
* Drew John, state representative
* Adam Kwasman, former state representative
* Vince Leach, state representative
* J. D. Mesnard, house speaker
* Becky Nutt, state representative
* Bob Thorpe, state representative
* Kelly Townsend, house majority whip
* Steve Yarbrough, Senate President
* Kimberly Yee, senate majority leader
Organizations
* Family Research Council Action PAC
* Gun Owners of America
* National Border Patrol Council
* National Republican Congressional Committee
* Tea Party Express
Individuals
* Josh Bernstein, conservative talk show host
* David Bossie, deputy campaign manager for Donald Trump's 2016 presidential campaign

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Wendy Rogers | 30,180 | 43.7 |
| | Republican | Steve Smith | 25,552 | 37.0 |
| | Republican | Tiffany Shedd | 13,260 | 19.2 |
| Total votes | Total votes | Total votes | 68,992 | 100.0 |

### Libertarian primary
#### Candidates

* Zhani Doko (write-in candidate)

### General election
#### Endorsements

Labor unions
* AFL-CIO
* Communications Workers of America
* International Brotherhood of Boilermakers
* International Brotherhood of Teamsters
Organizations
* Blue Dog Coalition
* Democratic Congressional Campaign Committee "Frontline" Program
* End Citizens United
* New Democrat Coalition
Newspapers
* Arizona Daily Star
U.S. representatives
* Dana Rohrabacher, U.S. representative from California's 48th congressional district (1989–present)
Organizations
* Courageous Conservatives PAC
* National Republican Congressional Committee "Young Guns" Program
* NRA Political Victory Fund
* Susan B. Anthony List
* Tea Party Nation

#### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | Tom O'Halleran (D) | Wendy Rogers (R) | Other | Undecided |
| 0ptimus/DDHQ | October 31 – November 1, 2018 | 756 | ± 3.6% | 48% | 45% | 1% | 6% |
| American Viewpoint (R) | October 16–18, 2018 | 400 | ± 4.9% | 46% | 46% | – | 5% |
| Go Right Strategies (R-Rogers) | October 9–10, 2018 | 943 | ± 3.0% | 38% | 44% | – | 18% |
| Go Right Strategies (R-Rogers) | September 27–28, 2018 | 738 | ± 4.0% | 36% | 39% | – | 24% |

#### Predictions

| Source | Ranking | As of |
| The Cook Political Report | Lean D | November 5, 2018 |
| Inside Elections | Lean D | November 5, 2018 |
| Sabato's Crystal Ball | Likely D | November 5, 2018 |
| RCP | Tossup | November 5, 2018 |
| Daily Kos | Likely D | November 5, 2018 |
| 538 | Likely D | November 7, 2018 |
| CNN | Lean D | October 31, 2018 |
| Fox News | Lean D | September 21, 2018 |
| Politico | Lean D | November 2, 2018 |

#### Results

Arizona's 1st congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Democratic | Tom O'Halleran (incumbent) | 143,240 | 53.8 |
| | Republican | Wendy Rogers | 122,784 | 46.1 |
| | Independent | David Shock (write-in) | 65 | 0.1 |
| Majority | Majority | Majority | 20,456 | 7.7 |
| Total votes | Total votes | Total votes | 266,089 | 100.0 |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## District 2

The 2nd district is based in the southeastern corner of Arizona and includes Cochise County and parts of suburban Tucson. Incumbent Republican Martha McSally, who had represented the district since 2015, did not run for re-election, instead running for the U.S. Senate. She was re-elected with 57% of the vote in 2016, and the district had a PVI of R+1.

### Republican primary
#### Candidates
##### Nominee

* Lea Márquez Peterson, president of the Tucson Hispanic Chamber of Commerce

##### Eliminated in primary

* Brandon Martin, Army instructor
* Danny Morales, former Douglas city councilman
* Casey Welch

#### Withdrew

* Martha McSally, incumbent (running for the U.S. Senate)
* Marilyn Wiles

#### Declined

* J. Christopher Ackerley, former state representative
* Steve Christy, Pima County Supervisor
* Todd Clodfelter, state representative
* David Gowan, former state representative
* Gail Griffin, former state representative
* Shelley Kais, candidate for state senate in 2016
* Ally Miller, Pima County Supervisor
* Ethan Orr, former state representative

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Lea Márquez Peterson | 23,571 | 34.2 |
| | Republican | Brandon Martin | 19,809 | 28.7 |
| | Republican | Casey Welch | 14,499 | 21.0 |
| | Republican | Daniel Morales, Jr. | 11,135 | 16.1 |
| Total votes | Total votes | Total votes | 69,014 | 100.0 |

### Democratic primary

This district was one of 80 Republican-held House districts targeted by the Democratic Congressional Campaign Committee.

#### Candidates
##### Nominee

* Ann Kirkpatrick, former U.S. Representative for Arizona's 1st District and nominee for U.S. Senate in 2016

##### Eliminated in primary

* Matt Heinz, former state representative, candidate for 8th district in 2012 and nominee for this seat in 2016
* Billy Kovacs, operations manager of Hotel Congress
* Mary Matiella, former assistant secretary of the Army
* Barbara Sherry
* Bruce Wheeler, former state representative
* Yahya Yuksel

##### Withdrawn

* Charlie Verdin, small businessman

##### Declined

* Brian Bickel, candidate for Pima County Supervisor in 2016
* Randall Friese, state representative
* Lou Jordan, retired U.S. Army colonel
* Jeff Latas, retired air force fighter pilot and candidate for AZ-08 in 2006
* Joshua Polacheck, foreign service officer
* Victoria Steele, former state representative and candidate for this seat in 2016

#### Endorsements

U.S. Senators
* Dennis DeConcini, former U.S. Senator (D-AZ)
State legislators
* Olivia Cajero Bedford, state senator
* David Bradley, state senator
* Daniel Hernández Jr., state representative
Labor unions
* American Federation of Teachers
* International Association of Machinists and Aerospace Workers
* International Brotherhood of Electrical Workers
Organizations
* Victory Fund
U.S. representatives
* Ron Barber, U.S. representative from Arizona's 2nd congressional district (2012–2015)
* Ruben Gallego, U.S. representative from Arizona's 7th congressional district (2015–present)
* Gabby Giffords, U.S. representative from Arizona's 8th congressional district (2007–2012)
State legislators
* Andrea Dalessandro, state senator
* Randy Friese, state representative
Labor unions
* Air Line Pilots Association
* American Federation of State, County and Municipal Employees
* American Physical Therapy Association
* American Postal Workers Union
* American Society of Anesthesiologists
* Association of Professional Flight Attendants
* International Alliance Theatrical Stage Employees
* International Association of Bridge, Structural, Ornamental and Reinforcing Iron Workers
* International Association of Sheet Metal, Air, Rail and Transportation Workers
* International Brotherhood of Boilermakers
* International Brotherhood of Teamsters
* International Union of Operating Engineers
* Laborers’ International Union of North America
* Marine Engineers' Beneficial Association
* National Air Traffic Controllers Association
* National Association of Letter Carriers
* National Association of Postal Supervisors
* Professional Aviation Safety Specialists
* Transport Workers Union of America
* UNITE HERE
* United Association
* United Food and Commercial Workers International Union
* United Transportation Union
Organizations
* American Association for Justice
* Council for a Livable World
* EMILY's List
* End Citizens United
* Feminist Majority
* NARAL Pro-Choice America
* National Committee to Preserve Social Security and Medicare
* National Organization for Women
* New Democrat Coalition
* Planned Parenthood Action Fund
* Stonewall Democrats of Arizona
Organizations
* Justice Democrats

#### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | Randy Friese | Matt Heinz | Ann Kirkpatrick | Billy Kovacs | Mary Matiella | Bruce Wheeler | Other | Undecided |
| FM3 Research (D-Heinz) | August 1–2, 2018 | 402 | ± 4.9% | – | 31% | 26% | – | – | – | 13% | 29% |
| FM3 Research (D-Heinz) | April 29 – May 3, 2018 | 400 | ± 4.9% | – | 27% | 23% | 4% | 6% | 4% | – | 36% |
| Public Policy Polling (D-Heinz) | May 5–7, 2017 | 392 | ± 5.0% | 6% | 40% | 30% | – | – | – | – | 24% |

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Ann Kirkpatrick | 33,938 | 41.8 |
| | Democratic | Matt Heinz | 23,992 | 29.6 |
| | Democratic | Mary Matiella | 7,606 | 9.4 |
| | Democratic | Bruce Wheeler | 6,814 | 8.4 |
| | Democratic | Billy Kovacs | 5,350 | 6.6 |
| | Democratic | Barbara Sherry | 2,074 | 2.6 |
| | Democratic | Yahya Yuksel | 1,319 | 1.6 |
| Total votes | Total votes | Total votes | 81,093 | 100.0 |

### General election
#### Endorsements

Organizations
* BIPAC
* Maggie's List
* National Republican Congressional Committee "Young Guns" Program
U.S. representatives
* Ron Barber, U.S. representative from Arizona's 2nd congressional district (2012–2015)
* Ruben Gallego, U.S. representative from Arizona's 7th congressional district (2015–present)
* Gabby Giffords, U.S. representative from Arizona's 8th congressional district (2007–2012)
State legislators
* Andrea Dalessandro, state senator
* Randy Friese, state representative
Labor unions
* AFL-CIO
* Air Line Pilots Association
* American Federation of State, County and Municipal Employees
* American Physical Therapy Association
* American Postal Workers Union
* American Society of Anesthesiologists
* Association of Professional Flight Attendants
* Communications Workers of America
* International Alliance Theatrical Stage Employees
* International Association of Bridge, Structural, Ornamental and Reinforcing Iron Workers
* International Association of Sheet Metal, Air, Rail and Transportation Workers
* International Brotherhood of Boilermakers
* International Brotherhood of Teamsters
* International Union of Operating Engineers
* Laborers’ International Union of North America
* Marine Engineers' Beneficial Association
* National Air Traffic Controllers Association
* National Association of Letter Carriers
* National Association of Postal Supervisors
* Professional Aviation Safety Specialists
* Transport Workers Union of America
* UNITE HERE
* United Association
* United Food and Commercial Workers International Union
* United Transportation Union
Organizations
* American Association for Justice
* Council for a Livable World
* Democratic Congressional Campaign Committee "Red to Blue" Program
* EMILY's List
* End Citizens United
* Everytown for Gun Safety
* Feminist Majority
* MoveOn
* NARAL Pro-Choice America
* National Committee to Preserve Social Security and Medicare
* National Organization for Women
* New Democrat Coalition
* Planned Parenthood Action Fund
* Stonewall Democrats of Arizona
Newspapers
* Arizona Daily Star

#### Debates

* Complete video of debate, October 11, 2018

#### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | Lea Marquez-Peterson (R) | Ann Kirkpatrick (D) | Undecided |
| NYT Upshot/Siena College | September 26 – October 1, 2018 | 502 | ± 4.5% | 39% | 50% | 11% |
| Public Policy Polling (D-Heinz) | February 8–10, 2018 | 841 | ± 3.4% | 34% | 43% | 23% |
With Heinz
| Poll source | Date(s) administered | Sample size | Margin of error | Lea Marquez-Peterson (R) | Matt Heinz (D) | Undecided |
| Public Policy Polling (D-Heinz) | February 8–10, 2018 | 841 | ± 3.4% | 31% | 45% | 24% |
| Poll source | Date(s) administered | Sample size | Margin of error | Martha McSally (R) | Matt Heinz (D) | Undecided |
| Public Policy Polling (D-Heinz) | May 5–7, 2017 | 944 | ± N/A | 44% | 48% | 8% |
| Poll source | Date(s) administered | Sample size | Margin of error | Martha McSally (R) | Ann Kirkpatrick (D) | Undecided |
| Public Policy Polling (D) | October 6–8, 2017 | 714 | ± 3.7% | 44% | 44% | — |
| Public Policy Polling (D-Heinz) | May 5–7, 2017 | 944 | ± N/A | 44% | 48% | 8% |

#### Predictions

| Source | Ranking | As of |
| The Cook Political Report | Lean D (flip) | November 5, 2018 |
| Inside Elections | Lean D (flip) | November 5, 2018 |
| Sabato's Crystal Ball | Likely D (flip) | November 5, 2018 |
| RCP | Lean D (flip) | November 5, 2018 |
| Daily Kos | Likely D (flip) | November 5, 2018 |
| 538 | Safe D (flip) | November 7, 2018 |
| CNN | Likely D (flip) | October 31, 2018 |
| Fox News | Lean D (flip) | September 21, 2018 |
| Politico | Lean D (flip) | November 2, 2018 |

#### Results

Arizona's 2nd congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Democratic | Ann Kirkpatrick | 161,000 | 54.7 |
| | Republican | Lea Márquez Peterson | 133,083 | 45.2 |
| | Independent | Jordan Flayer (write-in) | 50 | 0.1 |
| | Republican | Melissa Grable (write-in) | 19 | 0.0 |
| Majority | Majority | Majority | 27,917 | 9.5 |
| Total votes | Total votes | Total votes | 294,152 | 100.0 |
| | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican |

## District 3

The third district is based in Tucson and stretches along the southern border of Arizona including Yuma, rural portions of Maricopa County such as Gila Bend, and the western suburbs of Phoenix including Avondale, Buckeye, Goodyear, and parts of Litchfield Park. has represented this district since 2002, and ran unopposed in 2016. Incumbent Democrat Raúl Grijalva, who had represented the district since 2003, ran for re-election. He was re-elected with 99% of the vote in 2016, and the district had a PVI of D+13.

### Democratic primary
#### Candidates
##### Nominee

* Raúl Grijalva, incumbent U.S. Representative

##### Eliminated in primary

* Joshua Garcia (write-in candidate)

#### Endorsements

Labor unions
* International Brotherhood of Teamsters

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Raúl Grijalva (incumbent) | 45,186 | 99.8 |
| | Write-in | Write-in | 81 | 0.2 |
| Total votes | Total votes | Total votes | 45,267 | 100.0 |

### Republican primary
#### Candidates
##### Nominee

* J. Nicholas Pierson, financial planner and community organizer

##### Eliminated in primary

* Sergio Arellano, veteran
* Edna San Miguel, schoolteacher

##### Withdrawn

* Bill Abatecola, businessman (endorsed Arellano)

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | J. Nicholas Pierson | 13,090 | 49.9 |
| | Republican | Sergio Arellano | 7,400 | 28.2 |
| | Republican | Edna San Miguel | 5,756 | 21.9 |
| Total votes | Total votes | Total votes | 26,246 | 100.0 |

### General election
#### Endorsements

Labor unions
* AFL-CIO
* Communications Workers of America
* International Brotherhood of Teamsters
Organizations
* Congressional Progressive Caucus
* End Citizens United
* Justice Democrats
* Stonewall Democrats of Arizona
Newspapers
* Arizona Daily Star

#### Results

Arizona's 3rd congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Democratic | Raúl Grijalva (incumbent) | 114,650 | 63.9 |
| | Republican | Nicolas Pierson | 64,868 | 36.1 |
| Majority | Majority | Majority | 49,782 | 27.8 |
| Total votes | Total votes | Total votes | 179,518 | 100.0 |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## District 4

The fourth district takes up most of rural northwestern and western Arizona and includes Kingman, Lake Havasu City, Prescott, and San Tan Valley. Incumbent Republican Paul Gosar, who had represented the district since 2011, ran for re-election. He was re-elected with 71% of the vote in 2016, and the district had a PVI of R+21, making it the most Republican district in Arizona.

### Republican primary
#### Candidates
##### Nominee

* Paul Gosar, incumbent U.S. Representative

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Paul Gosar (incumbent) | 94,092 | 100.0 |
| Total votes | Total votes | Total votes | 94,092 | 100.0 |

### Democratic primary
#### Candidates
##### Nominee

* David Brill, Manager of Primary Care services for the Northern Arizona Veterans Administration

##### Eliminated in primary

* Delina Disanto, finance director and registered nurse
* Ana Maria Perez (write-in candidate)

#### Endorsements

Labor unions
* International Brotherhood of Teamsters

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | David Brill | 19,048 | 52.4 |
| | Democratic | Delina Disanto | 17,256 | 47.5 |
| | Write-in | Write-in | 49 | 0.1 |
| Total votes | Total votes | Total votes | 36,353 | 100.0 |

### Green primary
#### Candidates
##### Nominee

* Haryaksha Gregor Knauer

#### Primary results

Green primary results :
| Party | Party | Candidate | Votes | % |
| | Green | Haryaksha Gregor Knauer | 323 | 100.0 |
| Total votes | Total votes | Total votes | 323 | 100.0 |

### General election
#### Campaign

This race received national media coverage after Democratic nominee David Brill aired television advertisements in which six of Republican incumbent Paul Gosar's nine siblings each condemned their brother and endorsed Brill, imploring residents of the fourth district to vote their brother out of office. Gosar responded to this advert with a tweet in which he dismissed his siblings' criticisms and characterized them as "disgruntled Hillary supporters" who "put political ideology before family".

#### Endorsements

Organizations
* House Freedom Caucus
Labor unions
* AFL-CIO
* International Brotherhood of Teamsters
Organizations
* Indivisible

#### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | Paul Gosar (R) | David Brill (D) | Haryaksha Gregor Knauer (G) | Undecided |
| OH Predictive Insights | September 25, 2018 | 370 | ± 5.09% | 57% | 25% | 2% | 16% |

#### Results

Arizona's 4th congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Republican | Paul Gosar (incumbent) | 188,842 | 68.2 |
| | Democratic | David Brill | 84,521 | 30.5 |
| | Green | Haryaksha Gregor Knauer | 3,672 | 1.3 |
| Majority | Majority | Majority | 104,321 | 37.7 |
| Total votes | Total votes | Total votes | 277,035 | 100.0 |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## District 5

The 5th district is based in the East Valley region of suburban Phoenix and includes Gilbert and Queen Creek, as well as portions of Chandler and Mesa. Incumbent Republican Andy Biggs, who had represented the district since 2017, ran for re-election. He was elected with 64% of the vote in 2016, and the district had a PVI of R+15.

### Republican primary
#### Candidates
##### Nominee

* Andy Biggs, incumbent U.S. Representative

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Andy Biggs (incumbent) | 86,418 | 100.0 |
| Total votes | Total votes | Total votes | 86,418 | 100.0 |

### Democratic primary
#### Candidates
##### Nominee

* Joan Greene, business owner

##### Eliminated in primary

* Jose Torres, engineer and businessman

##### Withdrawn

* Lisa Chappelle
* Tony Margalis
* Scott Menor

#### Endorsements

Labor unions
* International Brotherhood of Teamsters
Organizations
* Stonewall Democrats of Arizona

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Joan Greene | 27,222 | 59.3 |
| | Democratic | Jose Torres | 18,671 | 40.7 |
| Total votes | Total votes | Total votes | 45,893 | 100.0 |

### General election
#### Endorsements

Organizations
* House Freedom Caucus
Labor unions
* AFL-CIO
* International Brotherhood of Teamsters
Organizations
* Stonewall Democrats of Arizona

#### Results

Arizona's 5th congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Republican | Andy Biggs (incumbent) | 186,037 | 59.4 |
| | Democratic | Joan Greene | 127,027 | 40.6 |
| Majority | Majority | Majority | 59,010 | 18.8 |
| Total votes | Total votes | Total votes | 313,064 | 100.0 |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## District 6

The sixth district is based in northeastern suburban Phoenix and is centered around Scottsdale, and also includes many affluent communities such as Fountain Hills and Paradise Valley. Incumbent Republican David Schweikert, who had represented the district since 2011, ran for re-election. He was re-elected with 62% of the vote in 2016, and the district had a PVI of R+9.

### Republican primary
#### Candidates
##### Nominee

* David Schweikert, incumbent U.S. Representative

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | David Schweikert (incumbent) | 83,406 | 100.0 |
| Total votes | Total votes | Total votes | 83,406 | 100.0 |

### Democratic primary

This district was one of 80 Republican-held House districts targeted by the Democratic Congressional Campaign Committee.

#### Candidates
##### Nominee

* Anita Malik, tech executive

##### Eliminated in primary

* Garrick McFadden, attorney
* Heather Ross, nurse practitioner

#### Endorsements

Labor unions
* International Brotherhood of Teamsters

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Anita Malik | 22,666 | 42.2 |
| | Democratic | Heather Ross | 20,203 | 37.6 |
| | Democratic | Garrick McFadden | 10,825 | 20.2 |
| Total votes | Total votes | Total votes | 53,694 | 100.0 |

### General election
#### Endorsements

Organizations
* House Freedom Caucus
Labor unions
* AFL-CIO
* International Brotherhood of Boilermakers
* International Brotherhood of Teamsters
Organizations
* End Citizens United
* Indivisible
* MoveOn
* Stonewall Democrats of Arizona

#### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | David Schweikert (R) | Anita Malik (D) | Undecided |
| NYT Upshot/Siena College | October 11–15, 2018 | 500 | ± 4.5% | 50% | 36% | 14% |

#### Predictions

| Source | Ranking | As of |
| The Cook Political Report | Likely R | November 5, 2018 |
| Inside Elections | Safe R | November 5, 2018 |
| Sabato's Crystal Ball | Likely R | November 5, 2018 |
| RCP | Likely R | November 5, 2018 |
| Daily Kos | Safe R | November 5, 2018 |
| 538 | Likely R | November 7, 2018 |
| CNN | Likely R | October 31, 2018 |
| Politico | Likely R | September 21, 2018 |

#### Results

Arizona's 6th congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Republican | David Schweikert (incumbent) | 173,140 | 55.2 |
| | Democratic | Anita Malik | 140,559 | 44.8 |
| Majority | Majority | Majority | 32,581 | 10.4 |
| Total votes | Total votes | Total votes | 313,699 | 100.0 |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## District 7

The seventh district is based in the city of Phoenix and also includes parts of Glendale and Tolleson. Incumbent Democrat Ruben Gallego, who had represented the district since 2015, ran for re-election. He was re-elected with 75% of the vote in 2016, and the district had a PVI of D+23, making it the most Democratic district in Arizona.

### Democratic primary
#### Candidates
##### Nominee

* Ruben Gallego, incumbent

##### Eliminated in primary

* Catherine Miranda, state senator

#### Endorsements

Labor unions
* International Brotherhood of Teamsters
Organizations
* Stonewall Democrats of Arizona

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Ruben Gallego (incumbent) | 32,231 | 74.8 |
| | Democratic | Catherine Miranda | 10,856 | 25.2 |
| Total votes | Total votes | Total votes | 43,087 | 100.0 |

### Republican primary

No Republican candidate filed to run.

### General election
#### Endorsements

Labor unions
* AFL-CIO
* Communications Workers of America
* International Brotherhood of Boilermakers
* International Brotherhood of Teamsters
Organizations
* Congressional Progressive Caucus
* End Citizens United
* Stonewall Democrats of Arizona
* VoteVets

#### Results

Arizona's 7th congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Democratic | Ruben Gallego (incumbent) | 113,044 | 85.6 |
| | Green | Gary Swing | 18,706 | 14.2 |
| | Republican | James "007" Bond IV (write-in) | 301 | 0.2 |
| Majority | Majority | Majority | 794,338 | 71.4 |
| Total votes | Total votes | Total votes | 132,051 | 100.0 |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

## District 8

The eighth district is based in the West Valley region of suburban Phoenix and includes the cities of El Mirage, Peoria, and Surprise, and also many retirement communities such as Sun City. Republican Trent Franks who had represented the district since 2003 resigned from Congress on December 8, 2017, after a controversy regarding surrogate mothers. Republican Debbie Lesko won the special election that took place on April 24, 2018, defeating Democratic nominee Hiral Tipirneni with 53% of the vote. The district had a PVI of R+13.

### Republican primary
#### Candidates
##### Nominee

* Debbie Lesko, incumbent U.S. Representative

##### Eliminated in primary

* Sandra E. Dowling, former Maricopa County School Superintendent

##### Declined

* Chad Allen, health care executive
* Travis Angry, activist
* Scott Allen Baker
* Jan Brewer, former Governor of Arizona (endorsed Debbie Lesko)
* Cathy Carlat, Mayor of Peoria, Arizona
* Kevin Engholdt, consultant
* Trent Franks, former U.S. Representative
* Clint Hickman, Maricopa County Supervisor
* David Lien, teacher
* Georgia Lord, former mayor of Goodyear, Arizona
* Phil Lovas, former state representative
* Steve Montenegro, state senator
* Jon Ritzheimer, activist
* Steven Sawdy (write-in)
* Bob Stump, former Arizona Corporation Commissioner
* Christopher Sylvester, navy veteran
* Kimberly Yee, state senator

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Debbie Lesko (incumbent) | 73,776 | 77.2 |
| | Republican | Sandra E. Dowling | 21,825 | 22.8 |
| Total votes | Total votes | Total votes | 95,601 | 100.0 |

### Democratic primary
#### Candidates
##### Nominee

* Hiral Tipirneni, physician and nominee for this seat in 2018 (special)

##### Removed from the ballot

* Bob Musselwhite
* Robert Olsen

##### Declined

* Robert Kyle Schuster
* Brianna Westbrook, political activist and LGBTQ community leader (running for Arizona state senate)

#### Endorsements

Labor unions
* International Brotherhood of Teamsters

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Hiral Tipirneni | 52,215 | 100.0 |
| Total votes | Total votes | Total votes | 52,215 | 100.0 |

### Independent candidates
#### Not on the ballot

* Augie Beyer

### General election
#### Campaign

The Lesko campaign was criticized for producing yard sign attacking Tipirneni as a "fake doctor" and as a "phony." on TV ads. These signs were taken down, but after Lesko accused Tipirneni of professional dishonesty during a TV appearance, the Arizona Medical Association withdrew its endorsement of Lesko.

#### Endorsements

Organizations
* Arizona Medical Association
* House Freedom Caucus
* Maggie's List
* Susan B. Anthony List
Labor unions
* AFL-CIO
* Communications Workers of America
* International Brotherhood of Boilermakers
* International Brotherhood of Teamsters
Organizations
* Democratic Congressional Campaign Committee "Red to Blue" Program
* EMILY's List
* End Citizens United
* Indivisible
* MoveOn
* Stonewall Democrats of Arizona

#### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | Debbie Lesko (R) | Hiral Tipirneni (D) | Undecided |
| Lake Research Partners (D-Tipirneni) | September 24–26, 2018 | 400 | ± 4.9% | 48% | 44% | 8% |
| Lake Research Partners (D-Tipirneni) | August 7–13, 2018 | 400 | – | 49% | 40% | 10% |

#### Predictions

| Source | Ranking | As of |
| The Cook Political Report | Likely R | November 5, 2018 |
| Inside Elections | Likely R | November 5, 2018 |
| Sabato's Crystal Ball | Likely R | November 5, 2018 |
| RCP | Likely R | November 5, 2018 |
| Daily Kos | Safe R | November 5, 2018 |
| 538 | Likely R | November 7, 2018 |
| CNN | Likely R | October 31, 2018 |
| Politico | Likely R | September 21, 2018 |

#### Results

In the general election, Lesko won a full term, again defeating Tipirneni.
Arizona's 8th congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Republican | Debbie Lesko (incumbent) | 168,835 | 55.5 |
| | Democratic | Hiral Tipirneni | 135,569 | 44.5 |
| | New Paradigm Party | Steven Hummel (write-in) | 13 | 0.0 |
| Majority | Majority | Majority | 33,266 | 11.0 |
| Total votes | Total votes | Total votes | 304,417 | 100.0 |
| | Republican hold | Republican hold | Republican hold | Republican hold |

## District 9

The ninth district is based in suburban Phoenix and is centered around Tempe, and also includes portions of Chandler, Mesa, and Scottsdale. Incumbent Democrat Kyrsten Sinema, who had represented the district since 2013, did not seek re-election, instead running for U.S. Senate. She was re-elected with 61% of the vote in 2016, and the district had a PVI of D+4, making it moderately competitive.

### Democratic primary
#### Candidates
##### Nominee

* Greg Stanton, Mayor of Phoenix

##### Not on the ballot

* Talia Fuentes, 2016 Democratic nominee for the 5th district

##### Declined

* Chad Campbell, former state house minority leader
* Andrei Cherny, former Arizona Democratic Party chair and candidate for this seat in 2012
* Katie Hobbs, state senate minority leader (running for secretary of state)
* Lauren Kuby, Tempe City Councilmember (endorsed Stanton)
* Juan Mendez, state senator
* Harry Mitchell, former U.S. Representative (endorsed Stanton)
* Mark Mitchell, Mayor of Tempe and son of former Rep Harry Mitchell (endorsed Stanton)
* Laura Pastor, Phoenix City Council member and daughter of former Rep Ed Pastor
* David Schapira, Tempe City Councilmember (running for Superintendent of Public Instruction) (endorsed Stanton)
* Andrew Sherwood, former state senator
* Tom Simplot, former Phoenix City Council member
* Kyrsten Sinema, incumbent U.S. Representative (running for US Senate)
* Corey Woods, former Tempe city councilmember (endorsed Stanton)

#### Endorsements

Labor unions
* International Brotherhood of Teamsters
Organizations
* Stonewall Democrats of Arizona

#### Primary results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Greg Stanton | 59,066 | 100.0 |
| Total votes | Total votes | Total votes | 59,066 | 100.0 |

### Republican primary

This district was one of 36 Democratic-held House districts targeted by the National Republican Congressional Committee.

#### Candidates
##### Nominee

* Steve Ferrara, retired Navy Chief Medical Officer

##### Eliminated in primary

* Irina Baroness von Behr, pilot and Tempe City Council candidate in 2016
* David Giles, engineer, business consultant and nominee for this seat in 2016
Declined
* Sal Diciccio, Phoenix City Council member
* Hugh Hallman, former mayor of Tempe and candidate for state treasurer in 2014
* Dean Martin, former State Treasurer of Arizona

#### Endorsements

Organizations
* National Republican Congressional Committee

#### Primary results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Steve Ferrara | 31,006 | 59.9 |
| | Republican | David Giles | 16,722 | 32.3 |
| | Republican | Irina Baroness von Behr | 4,020 | 7.8 |
| Total votes | Total votes | Total votes | 51,748 | 100.0 |

### Libertarian primary
#### Candidates
##### Withdrawn

* Jenn Gray (write-in candidate)

### General election
#### Endorsements

Labor unions
* AFL-CIO
* Communications Workers of America
* International Brotherhood of Boilermakers
* International Brotherhood of Teamsters
Organizations
* End Citizens United
* New Democrat Coalition
* Stonewall Democrats of Arizona
Organizations
* National Republican Congressional Committee "Young Guns" Program
* With Honor Fund

#### Predictions

| Source | Ranking | As of |
| The Cook Political Report | Safe D | November 5, 2018 |
| Inside Elections | Safe D | November 5, 2018 |
| Sabato's Crystal Ball | Safe D | November 5, 2018 |
| RCP | Likely D | November 5, 2018 |
| Daily Kos | Safe D | November 5, 2018 |
| 538 | Safe D | November 7, 2018 |
| CNN | Likely D | October 31, 2018 |
| Politico | Likely D | November 2, 2018 |

#### Results

Arizona's 9th congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Democratic | Greg Stanton | 159,583 | 61.1 |
| | Republican | Steve Ferrara | 101,662 | 38.9 |
| Majority | Majority | Majority | 57,921 | 22.2 |
| Total votes | Total votes | Total votes | 261,245 | 100.0 |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold |