# 2010 United States Senate election in Colorado

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vte :
The 2010 United States Senate election in Colorado took place on November 2, 2010, alongside other elections to the United States Senate in other states as well as elections to the United States House of Representatives and various state and local elections. In December 2008, President-elect Barack Obama nominated incumbent U.S. Senator Ken Salazar as Secretary of the Interior. After Salazar resigned from his seat, Democratic governor Bill Ritter appointed Denver Public Schools Superintendent Michael Bennet to fill the seat.
Bennet won a full term, defeating former state House speaker Andrew Romanoff in the Democratic primary, and Republican nominee Ken Buck in the general election. With a margin of 1.7%, this election was the second-closest race of the 2010 Senate election cycle after the concurrent one in Illinois.

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

* Michael Bennet, incumbent U.S. Senator

#### Eliminated in primary

* Andrew Romanoff, former speaker of the Colorado House of Representatives

### Endorsements

Bennet
* President Barack Obama
* U.S. Senator Russ Feingold
* Congresswoman Diana DeGette
* Congressman Ed Perlmutter
* Congresswoman Betsy Markey
* U.S. Senator Mark Udall
* Congressman Jared Polis
* Congressman John Salazar
* Former U.S. Senator Gary Hart
* Governor Bill Ritter
Romanoff
* Former president Bill Clinton

### Polling

| Poll Source | Dates Administered | Michael Bennet | Andrew Romanoff | Undecided |
| The Tarrance Group | September 16–17, 2009 | 41% | 27% | 32% |
| Public Policy Polling | May 19, 2010 | 46% | 31% | 23% |
| Survey USA | June 15–17, 2010 | 53% | 36% | 11% |
| Survey USA | August 1, 2010 | 45% | 48% | 7% |
| Public Policy Polling | August 7–8, 2010 | 49% | 43% | 9% |

### Results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | Michael Bennet (incumbent) | 184,714 | 54.15% |
| | Democratic | Andrew Romanoff | 156,419 | 45.85% |
| Total votes | Total votes | Total votes | 341,133 | 100.0% |

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

* Ken Buck, Weld County District Attorney

#### Eliminated in primary

* Jane Norton, former Lieutenant Governor of Colorado

#### Eliminated in convention

* Cleve Tidwell, businessman
* Robert Greenheck
* Steve Barton

#### Withdrew

* Tom Wiens, former state senator

#### Declined

* Bob Beauprez, former U.S. Representative for Colorado's 7th congressional district
* Troy Eid, U.S. Attorney for United States District Court for the District of Colorado
* Ryan Frazier, Aurora city councilman

### Endorsements

* Jim DeMint, U.S. Senator
* Erick Erickson, blogger
* Tom Wiens, state senator
According to her website:
* American Conservative Union
* Family Research Council
* Susan B. Anthony List
* Bill Owens, Governor
* Sarah Palin, former Governor
* William L. Armstrong, former U.S. Senator
* Hank Brown, former U.S. Senator
* Sam Brownback, U.S. Senator
* Tom Coburn, U.S. Senator
* Bob Beauprez, former U.S. Congressman
* John Suthers, State Attorney General
* Mark Hillman, former state treasurer
* Jan Brewer, Arizona Governor
* Wayne Allard, Former U.S. Senator
* Orrin Hatch, U.S. Senator
* Josh Penry, state senator
* United States Chamber of Commerce

### Polling

| Poll Source | Dates Administered | Ken Buck | Jane Norton |
| The Tarrance Group | September 16–17, 2009 | 15% | 45% |
| Public Policy Polling | March 3, 2010 | 17% | 34% |
| Magellan | March 14, 2010 | 13% | 41% |
| Magellan | April 19, 2010 | 32% | 29% |
| Public Policy Polling | May 19, 2010 | 26% | 31% |
| Magellan | June 8, 2010 | 42% | 32% |
| Survey USA | June 15–17, 2010 | 53% | 37% |
| Public Opinion Strategies | June 20–21, 2010 | 33% | 39% |
| Survey USA | August 1, 2010 | 50% | 41% |
| Public Policy Polling | August 7–8, 2010 | 43% | 45% |

### Results

Republican Primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Ken Buck | 211,099 | 51.57% |
| | Republican | Jane Norton | 198,231 | 48.43% |
| Total votes | Total votes | Total votes | 409,330 | 100.0% |

## Libertarian primary
### Candidates
#### Nominee

* Mac Stringer

#### Eliminated in primary

* John Finger

### Results

Libertarian Primary results :
| Party | Party | Candidate | Votes | % |
| | Libertarian | Mac Stringer | 1,186 | 52.45% |
| | Libertarian | John Finger | 1,075 | 47.55% |
| Total votes | Total votes | Total votes | 2,261 | 100.0% |

## General election
### Candidates
#### Major

* Michael Bennet (D), incumbent U.S. Senator
* Ken Buck (R), Weld County DA

#### Minor

* Bob Kinsey (G) (campaign site, archived November 4, 2010, PVS)
* Charley Miller (I) (campaign site, PVS)
* J. Moromisato (I) (campaign site, PVS)
* Jason Napolitano (I) (PVS)
* Mac Stringer (L) (campaign site Archived October 29, 2010, at the Wayback Machine, PVS)
* Bruce E. Lohmiller (G) (Write-in) (Congress.org)
* Michele M. Newman (I) (Write-in)
* Robert Rank (R) (Write-in) campaign site, YouTube campaign video
Source: Official Candidate List

### Campaign

This was one of the most expensive elections in the nation, as more than $30 million was spent by outside organizations. Conservative third party groups hammered Bennet for voting 92% of the time with the Democratic leadership, including voting for healthcare reform and the stimulus package. Liberal third party groups called Buck extremist. Bennet focused on attacking Buck's views on abortion, which he believed should be banned including those of cases of rape and incest. He was also attacked for wanting to eliminate the Seventeenth Amendment and refusing to prosecute an alleged rapist as Weld County district attorney. Planned Parenthood mounted a mail campaign, targeting women voters with the warning that "Colorado women can't trust Ken Buck." Bennet won the women vote by 17 points according to exit polls. After the election, Buck conceded to the Denver Post that the main reason why he lost is because of social issues.

### Debates

* September 12: Sponsored by Club 20 in Grand Junction

### Predictions

| Source | Ranking | As of |
| Cook Political Report | Tossup | October 26, 2010 |
| Inside Elections | Tossup | October 22, 2010 |
| RealClearPolitics | Tossup | October 26, 2010 |
| Sabato's Crystal Ball | Lean R (flip) | October 21, 2010 |
| CQ Politics | Tossup | October 26, 2010 |

### Polling

| Poll source | Date(s) administered | Michael Bennet (D) | Ken Buck (R) |
| Public Policy Polling | April 17–19, 2009 | 40% | 39% |
| Public Policy Polling | August 14–16, 2009 | 39% | 35% |
| Rasmussen Reports | September 9, 2009 | 43% | 37% |
| Rasmussen Reports | December 8, 2009 | 38% | 42% |
| Daily Kos/Research 2000 | January 11–13, 2010 | 41% | 38% |
| Rasmussen Reports | January 13, 2010 | 38% | 43% |
| Rasmussen Reports | February 2, 2010 | 41% | 45% |
| Rasmussen Reports | March 2, 2010 | 38% | 44% |
| Public Policy Polling | March 5–8, 2010 | 47% | 40% |
| Rasmussen Reports | April 5, 2010 | 40% | 44% |
| Rasmussen Reports | May 3, 2010 | 41% | 48% |
| Public Policy Polling | May 19, 2010 | 45% | 39% |
| Rasmussen Reports | June 7, 2010 | 41% | 46% |
| Survey USA | June 15–17, 2010 | 43% | 46% |
| Rasmussen Reports | July 8, 2010 | 39% | 48% |
| Rasmussen Reports | July 26, 2010 | 42% | 48% |
| Survey USA | August 1, 2010 | 43% | 43% |
| Public Policy Polling | August 10, 2010 | 46% | 43% |
| Rasmussen Reports | August 11, 2010 | 41% | 46% |
| Ipsos/Reuters | August 20–22, 2010 | 40% | 49% |
| Rasmussen Reports | August 30, 2010 | 44% | 47% |
| Rasmussen Reports | September 14, 2010 | 45% | 49% |
| CNN/Time | September 17–21, 2010 | 44% | 49% |
| Rasmussen Reports | September 27, 2010 | 43% | 51% |
| Rasmussen Reports | September 27, 2010 | 43% | 51% |
| McClatchy/Marist | September 26–28, 2010 | 42% | 50% |
| Survey USA | September 28–30, 2010 | 43% | 48% |
| Public Policy Polling | September 30 – October 2, 2010 | 46% | 45% |
| Rasmussen Reports | October 14, 2010 | 45% | 47% |
| Fox News/Pulse Opinion Research | October 16, 2010 | 45% | 46% |
| Ipsos/Reuters | October 18, 2010 | 45% | 48% |
| SurveyUSA | October 19–21, 2010 | 47% | 47% |
| Public Policy Polling | October 21–23, 2010 | 47% | 47% |
| Rasmussen Reports | October 25, 2010 | 44% | 48% |
| CNN/Time/Opinion Research | October 20–26, 2010 | 46% | 47% |
| Marist College | October 26–28, 2010 | 45% | 49% |
| Fox News/Pulse Opinion Research | October 30, 2010 | 46% | 50% |
| Public Policy Polling | October 30–31, 2010 | 48% | 49% |

### Fundraising

These totals reflect the campaign accounts of the candidates themselves, and do not include independent expenditures by other groups.
| Candidate (Party) | Receipts | Disbursements | Cash On Hand | Debt |
| Michael Bennet (D) | $11,463,661 | $10,698,578 | $763,541 | $887,692 |
| Ken Buck (R) | $3,827,432 | $3,011,656 | $1,039,994 | $100,000 |
| Source: Federal Election Commission |||||

### Results

United States Senate election in Colorado, 2010 :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Michael Bennet (incumbent) | 854,685 | 48.08% | −3.22% |
| | Republican | Ken Buck | 824,789 | 46.40% | −0.13% |
| | Green | Bob Kinsey | 38,884 | 2.19% | N/A |
| | Libertarian | Maclyn Stringer | 22,646 | 1.27% | +0.79% |
| | Independent | Jason Napolitano | 19,450 | 1.09% | N/A |
| | Independent | Charley Miller | 11,351 | 0.64% | N/A |
| | Independent | J. Moromisato | 5,780 | 0.33% | N/A |
| | Write-in | Write-in | 83 | 0.07% | N/A |
| Total votes | Total votes | Total votes | 1,777,668 | 100.0% | |
| | Democratic hold | Democratic hold | Democratic hold | Democratic hold | Democratic hold |

#### Counties that flipped from Democratic to Republican

* Garfield (largest municipality: Glenwood Springs)
* Bent (Largest city: Las Animas)
* Mineral (Largest city: Creede)
* Rio Grande (Largest city: Monte Vista)
* Archuleta (Largest city: Pagosa Springs)

#### Counties that flipped from Republican to Democratic

* Chaffee (largest city: Salida)
* Ouray (largest city: Ouray)