# 2020 United States Senate election in Colorado

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The 2020 United States Senate election in Colorado was held on November 3, 2020, to elect a member of the United States Senate to represent the State of Colorado, concurrently with the 2020 U.S. presidential election, as well as other elections to the United States Senate, elections to the United States House of Representatives and various state and local elections.
Under Colorado law, the filing deadline for U.S. Senate candidates was March 17, 2020, the third Tuesday in March of the election year; the primary election occurred on June 30. Incumbent senator Cory Gardner lost re-election to former governor John Hickenlooper. Gardner was unopposed in the Republican primary, and Hickenlooper defeated former State House Speaker Andrew Romanoff in the Democratic primary.
This race was one of two Republican-held U.S. Senate seats up for election in 2020 in a state President Trump lost in 2016; the other was in Maine. Many pollsters and pundits considered Gardner to be the most vulnerable Republican senator facing re-election in 2020 due to his narrow victory in 2014, the state's leftward shift, and Trump's unpopularity in the state.
As predicted, Hickenlooper easily defeated Gardner by a 9.3-point margin. However, Gardner did manage to outperform Donald Trump in the concurrent presidential election by roughly four points. This became the first election Gardner had lost in his political career as well as being the widest margin of loss for a Coloradan U.S. Senator since 1978. This was the third consecutive election where this seat flipped parties, and also the second consecutive election in which the incumbent senator lost re-election to a second term for this particular seat. At the age of 68, Hickenlooper is the oldest first term senator from Colorado.

## Background

Gardner was elected to the U.S. Senate in 2014, narrowly defeating incumbent Democratic senator Mark Udall in a very successful election year for Republicans. Gardner was widely considered vulnerable in 2020 due to Colorado's recent Democratic trend and his support for Trump. Polling showed that more voters had a negative view of Gardner compared to a positive one. Gardner also faced a four-year grassroots campaign across the state by progressive political activists to hold him accountable for his votes, featured a cardboard cutout dubbed "Cardboard Cory". The seat was expected to be highly competitive and the most likely Republican-held seat to flip Democratic. The Democratic nominee, former governor John Hickenlooper, had a consistent double-digit lead over Gardner in the polls.
Various minor scandals in the days leading up to the June 30 Democratic primary sparked speculation that Romanoff might win, but Hickenlooper had an advantage in name recognition, and harsh negative attacks by Romanoff reportedly led many state Democrats and voters to sour on him.

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

* Cory Gardner, incumbent U.S. senator

#### Withdrawn

* Margot Dupre, estate agent
* Gail Prentice, veteran and business owner

### Endorsements

U.S. presidents
* George W. Bush, 43rd president of the United States
* Donald Trump, 45th president of the United States
U.S. Executive Branch officials
* Gary L. Bauer, former United States Under Secretary of Education, Assistant to the President for Policy Development, United States Deputy Under Secretary of Education for Planning and Budget, and Member of the United States Commission on International Religious Freedom
* John Bolton, former United States National Security Advisor
* Nikki Haley, former United States Ambassador to the United Nations
Organizations
* Campaign for Working Families
* Huck PAC
* Republican Jewish Coalition
Other individuals
* Charles Koch, billionaire political activist

### Results

Republican primary results :
| Party | Party | Candidate | Votes | % |
| | Republican | Cory Gardner (incumbent) | 554,806 | 100.00% |
| Total votes | Total votes | Total votes | 554,806 | 100.00% |

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

* John Hickenlooper, former governor of Colorado and former candidate for president of the United States in 2020

#### Eliminated in primary

* Andrew Romanoff, former Speaker of the Colorado House of Representatives, candidate for U.S. Senate in 2010, and nominee for Colorado's 6th congressional district in 2014

#### Withdrawn

* Dan Baer, former executive director of the Colorado Department of Higher Education and former United States Ambassador to the Organization for Security and Cooperation in Europe (endorsed John Hickenlooper)
* Derrick Blanton
* Marcos Boyington, software engineer
* Diana Bray, psychologist and climate activist (endorsed Andrew Romanoff)
* Denise Burgess, businesswoman and Denver Metro Chamber of Commerce board member
* Ellen Burnes, Colorado State University professor and former chair of the Boulder County Democratic Party
* Lorena Garcia, community organizer
* David Goldfischer, associate professor at the Korbel School for International Studies at the University of Denver and national security advisor
* Mike Johnston, former state senator and candidate for Governor of Colorado in 2018
* Danielle Kombo, medical recruiter and businesswoman (endorsed Stephany Rose Spaulding)
* Dustin Leitzel, pharmacist
* Alice Madden, former majority leader of the Colorado House of Representatives
* Christopher Hawkins Critter Milton, 2020 Unity Party nominee for Colorado's 3rd congressional district
* Keith Pottratz, technician and veteran (endorsed Lorena Garcia)
* Stephany Rose Spaulding, professor at University of Colorado Colorado Springs and nominee for Colorado's 5th congressional district in 2018 (endorsed Lorena Garcia)
* Erik Underwood, entrepreneur and candidate for Governor of Colorado in 2018
* John F. Walsh, former U.S. Attorney for the District of Colorado (endorsed John Hickenlooper)
* Michelle Ferrigno Warren, nonprofit leader, immigration advocate, first time candidate
* Angela Williams, state senator (ran for re-election)
* Trish Zornio, biomedical scientist (endorsed John Hickenlooper)

#### Declined

* Diana DeGette, incumbent U.S. Representative (ran for re-election)
* Kerry Donovan, state senator (endorsed John Hickenlooper)
* Crisanta Duran, former speaker of the Colorado House of Representatives (ran for Colorado's 1st congressional district, then withdrew)
* Jena Griswold, Colorado Secretary of State
* Cary Kennedy, former Colorado State Treasurer
* Joe Neguse, incumbent U.S. representative for Colorado's 2nd congressional district (ran for re-election)
* Ed Perlmutter, incumbent U.S. representative for Colorado's 7th congressional district (endorsed John Hickenlooper)
* Joe Salazar, former state representative

### Endorsements

U.S. presidents
* Barack Obama, 44th president of the United States
Former U.S. Executive Branch officials
* Ken Salazar, former U.S. Interior Secretary and former U.S. senator (CO)
U.S senators
* Kamala Harris, 2020 vice presidential nominee, United States Senator from California (2017–2021)
* Amy Klobuchar, senator for Minnesota (2007–present), former 2020 presidential candidate.
* Elizabeth Warren, U.S. senator from Massachusetts (2013–present), former 2020 presidential candidate
U.S. representatives
* Ed Perlmutter, U.S. representative (CO)
State officials
* Roy Romer, former governor of Colorado
Local officials
* Brianna Buentello, state representative
* Leroy Garcia, president of the Colorado Senate
* Dylan Roberts, state representative
Newspapers
* The Durango Herald
Organizations
* 314 Action
* Bend the Arc: Jewish Action
* Congressional Black Caucus PAC
* Congressional Hispanic Caucus
* Council for a Livable World
* Democratic Majority for Israel PAC
* End Citizens United
* Everytown for Gun Safety
* Feminist Majority PAC
* Giffords
* J Street
* Joint Action Committee for Political Affairs
* League of Conservation Voters
* Let America Vote
* NARAL Pro-Choice America
* National Committee to Preserve Social Security and Medicare
* Sierra Club
* Students for Gun Legislation
State officials
* Peter Groff, former Colorado State Senate president and state representative
* Polly Baca, former state senator and state representative
Individuals
* Bill McKibben, environmentalist, lecturer, and founder of 350.org
* Marianne Williamson, author, former candidate for California's 33rd congressional district, former 2020 presidential candidate
Newspapers
* Sentinel Colorado
Organizations
* Climate Hawks Vote
* Our Revolution
* Progressive Democrats of America
* Sunrise Movement

### Polling

| Poll source | Date(s) administered | Sample size | Margin of error | Jena Griswold | John Hickenlooper | Mike Johnston | Andrew Romanoff | Other / Undecided |
| SurveyUSA | June 19–24, 2020 | 575 (LV) | ± 6.0% | – | 58% | – | 28% | 15% |
| Myers Research and Strategic Services | June 16–17, 2020 | 500 (LV) | ± 4.4% | – | 51% | – | 39% | – |
| Unspecified polling firm | October 2019 | – (LV) | – | – | 68% | – | 19% | – |
| | September 3, 2019 | Johnston withdraws from the race | Johnston withdraws from the race | Johnston withdraws from the race | Johnston withdraws from the race | Johnston withdraws from the race | Johnston withdraws from the race | Johnston withdraws from the race |
| Public Policy Polling (D) | August 28–29, 2019 | 509 (LV) | – | – | 60% | 3% | 9% | 27% |
| Public Policy Polling (D) | August 28–29, 2019 | 509 (LV) | – | – | 66% | – | 17% | 17% |
| | August 21, 2019 | Hickenlooper announces his candidacy | Hickenlooper announces his candidacy | Hickenlooper announces his candidacy | Hickenlooper announces his candidacy | Hickenlooper announces his candidacy | Hickenlooper announces his candidacy | Hickenlooper announces his candidacy |
| | August 9, 2019 | Griswold announces that she will not run | Griswold announces that she will not run | Griswold announces that she will not run | Griswold announces that she will not run | Griswold announces that she will not run | Griswold announces that she will not run | Griswold announces that she will not run |
| Garin-Hart-Yang Research Group | July 25–28, 2019 | 600 (LV) | – | 6% | 61% | 10% | 8% | 15% |
| Public Policy Polling (D) | July 12–14, 2019 | 561 (LV) | – | 4% | 44% | 3% | 12% | 38% |
Hypothetical polling :
| Poll source | Date(s) administered | Sample size | Margin of error | Dan Baer | John Hickenlooper | Undecided |
| Public Policy Polling (D) | August 28–29, 2019 | 509 (LV) | – | 11% | 72% | 17% |
| Poll source | Date(s) administered | Sample size | Margin of error | John Hickenlooper | Mike Johnston | Undecided |
| Public Policy Polling (D) | August 28–29, 2019 | 509 (LV) | – | 69% | 14% | 18% |
| Poll source | Date(s) administered | Sample size | Margin of error | John Hickenlooper | Alice Madden | Undecided |
| Public Policy Polling (D) | August 28–29, 2019 | 509 (LV) | – | 69% | 14% | 17% |
| Poll source | Date(s) administered | Sample size | Margin of error | John Hickenlooper | Angela Williams | Undecided |
| Public Policy Polling (D) | August 28–29, 2019 | 509 (LV) | – | 70% | 11% | 18% |

### Caucus

On March 7, 2020, the Colorado Democratic Party held a non-binding Senate primary preference poll at its caucus sites. Attendees could choose delegates to county and then state conventions. If a candidate received at least 30% of the delegates at the state convention they would be placed on the ballot. Some candidates were not listed because they instead chose to attempt to collect signatures to reach the ballot. Candidates needed 1,500 signatures from each congressional district. Hickenlooper and Underwood chose to do both. Romanoff collected the needed signatures as of March 8, 2020.

#### Caucus results

Romanoff was the only candidate to get more than 30% in the initial precinct caucuses. Hickenlooper withdrew from the assembly process soon afterward, choosing to qualify for the ballot exclusively by petition. Ballot access for assembly candidates will be decided at the state assembly. Caucus winners do not always receive the party's nomination; Romanoff won them in the 2010 Democratic primary for Colorado's Senate race, but Michael Bennet won the party's nomination that year.
The aggregate results of the various precinct caucuses on March 7, 2020, were:
| Candidate | Total raw votes | Percentage of vote won (%) |
| Andrew Romanoff | 8,629 | 54.98 |
| John Hickenlooper | 4,761 | 30.34 |
| Trish Zornio | 976 | 6.21 |
| Stephany Rose Spaulding | 771 | 4.91 |
| Uncommitted | 520 | 3.31 |
| Erik Underwood | 35 | 0.22 |

### Results

Democratic primary results :
| Party | Party | Candidate | Votes | % |
| | Democratic | John Hickenlooper | 585,826 | 58.65% |
| | Democratic | Andrew Romanoff | 412,955 | 41.35% |
| Total votes | Total votes | Total votes | 998,781 | 100.00% |

## Other candidates
### Libertarian primary
#### Nominee

* Raymon Doane, Libertarian nominee for Colorado's 1st congressional district in 2018

#### Eliminated in primary

* Gaylon Kent, author and perennial candidate

#### Results

Libertarian primary results :
| Party | Party | Candidate | Votes | % |
| | Libertarian | Raymon Doane | 3,477 | 62.41% |
| | Libertarian | Gaylon Kent | 2,094 | 37.59% |
| Total votes | Total votes | Total votes | 5,571 | 100.00% |

### Unity Party
#### Nominee

* Stephan "Chairman Seku" Evans, former candidate for mayor of Denver

#### Eliminated at Unity Party convention

* Joshua Rodriguez

#### Withdrawn

* Gary Swing, perennial candidate

### Write-in candidates
#### Declared

* Dan Doyle (Approval Voting Party)
* Bruce Lohmiller (Green Party)
* Theodore Rockwell, Steamboat Springs (independent)
* Michael Sanchez (independent)
* Danny Skelly, small business owner (independent)

#### Withdrawn

* Veronique Bellamy, former candidate for RTD board (Socialist Party)
* Joseph "Joey" Camp, performance artist (independent)
* Lisa Garcia (independent)
* Christopher K. Springer (independent)
* Donald George Willoughby (independent)
* Marti Wolf (independent)

## General election
### Debate

| Host | Date & time | Link(s) | Participants | Participants |
| Host | Date & time | Link(s) | John Hickenlooper | Cory Gardner |
| Colorado State University | October 13, 2020 6:00pm MDT | | Present | Present |

### Predictions

| Source | Ranking | As of |
| The Cook Political Report | Lean D (flip) | October 29, 2020 |
| Inside Elections | Lean D (flip) | October 28, 2020 |
| Sabato's Crystal Ball | Likely D (flip) | November 2, 2020 |
| Daily Kos | Likely D (flip) | October 30, 2020 |
| Politico | Lean D (flip) | November 2, 2020 |
| RCP | Lean D (flip) | October 23, 2020 |
| DDHQ | Likely D (flip) | November 3, 2020 |
| 538 | Likely D (flip) | November 2, 2020 |
| Economist | Likely D (flip) | November 2, 2020 |

### Post-primary endorsements

Organizations
* Citizens for Responsible Energy Solutions
* Susan B. Anthony List
* Tea Party Express
Newspapers
* The Gazette
U.S senators
* Michael Bennet, U.S. senator from Colorado (2009–present), former 2020 presidential candidate
Unions
* International Federation of Professional and Technical Engineers
* National Education Association
* SEIU Local 105
* United Auto Workers
* United Farm Workers
Organizations
* Black Economic Alliance
* Greater Metro Denver Ministerial Alliance
* Humane Society of the United States Legislative Fund
* MoveOn
* Natural Resources Defense Council Action Fund
* Population Connection

### Polling
#### Poll Results

| Poll source | Date(s) administered | Sample size | Margin of error | Cory Gardner (R) | John Hickenlooper (D) | Other / Undecided |
| Keating Research/Onsight Public Affairs/Colorado Sun | October 29 – November 1, 2020 | 502 (LV) | ± 4.4% | 42% | 53% | – |
| Data for Progress | October 27 – November 1, 2020 | 709 (LV) | ± 3.7% | 45% | 54% | 2% |
| Swayable | October 23 – November 1, 2020 | 443 (LV) | ± 6% | 43% | 57% | – |
| Morning Consult | October 22–31, 2020 | 727 (LV) | ± 4% | 44% | 52% | – |
| Morning Consult | October 11–20, 2020 | 788 (LV) | ± 3.5% | 42% | 50% | – |
| RBI Strategies & Research | October 12–16, 2020 | 502 (LV) | ± 4.4% | 39% | 53% | 7% |
| RMG Research/PoliticalIQ | October 9–15, 2020 | 800 (LV) | ± 3.5% | 42% | 51% | 7% |
| Civiqs/Daily Kos | October 11–14, 2020 | 1,013 (LV) | ± 3.6% | 42% | 53% | 3% |
| Keating Research/OnSight Public Affairs/Melanson | October 8–13, 2020 | 519 (LV) | ± 4.3% | 41% | 51% | 7% |
| Morning Consult | October 2–11, 2020 | 837 (LV) | ± 3.4% | 40% | 50% | – |
| YouGov/University of Colorado | October 5–9, 2020 | 800 (LV) | ± 4.64% | 40% | 48% | 12% |
| SurveyUSA | October 1–6, 2020 | 1,021 (LV) | ± 3.9% | 39% | 48% | 14% |
| Morning Consult | September 11–20, 2020 | 613 (LV) | ± (2% – 7%) | 42% | 49% | – |
| Morning Consult | September 8–17, 2020 | 599 (LV) | ± (2% – 4%) | 44% | 46% | – |
| Fabrizio Ward/Hart Research Associates | August 30 – September 5, 2020 | 800 (LV) | ± 3.5% | 46% | 51% | 4% |
| Global Strategy Group (D) | August 28 – September 1, 2020 | 800 (LV) | ± 3.5% | 42% | 52% | 5% |
| Morning Consult | August 21–30, 2020 | 638 (LV) | ± 4.0% | 39% | 48% | 13% |
| Morning Consult | August 16–25, 2020 | ≈600 (LV) | ± 4.0% | 39% | 48% | – |
| Public Policy Polling (D) | August 18–19, 2020 | 731 (V) | ± 3.2% | 42% | 51% | 7% |
| Morning Consult | August 6–15, 2020 | ≈600 (LV) | ± 4.0% | 38% | 49% | – |
| Morning Consult | July 27 – August 5, 2020 | ≈600 (LV) | ± 4.0% | 39% | 50% | – |
| Morning Consult | July 17–26, 2020 | 616 (LV) | ± 4.0% | 42% | 48% | 11% |
| Morning Consult | July 13–22, 2020 | ≈600 (LV) | ± 4.0% | 41% | 50% | – |
| Public Policy Polling | June 29–30, 2020 | 840 (V) | ± 3.4% | 40% | 51% | 9% |
| Keating Research/OnSight Public Affairs/Melanson | May 1–3, 2020 | 600 (LV) | ± 4.0% | 36% | 54% | 10% |
| Montana State University Bozeman | April 10–19, 2020 | 379 (LV) | ± 4.4% | 31% | 48% | 21% |
| Keating Research | October 10–14, 2019 | 500 (LV) | ± 4.4% | 42% | 53% | 5% |
| Emerson College | August 16–19, 2019 | 1,000 (RV) | ± 3.0% | 40% | 53% | 8% |
| Global Strategy Group (D) | August 13–14, 2019 | 617 (LV) | ± 3.9% | 39% | 49% | 13% |
| Public Policy Polling | August 8–11, 2019 | 739 (V) | ± 3.6% | 38% | 51% | 12% |
with generic Democrat
| Poll source | Date(s) administered | Sample size | Margin of error | Cory Gardner (R) | Generic Democrat | Other / Undecided |
| Global Strategy Group (D) | August 13–14, 2019 | 617 (LV) | ± 3.9% | 38% | 48% | 14% |
| Global Strategy Group | January 31 – February 4, 2019 | 818 (RV) | ± 3.4% | 40% | 51% | 9% |
| DFM Research | January 2–5, 2019 | 550 (A) | ± 4.2% | 38% | 46% | 16% |
| Change Research (D) | December 2–4, 2018 | 540 (LV) | ± 4.2% | 41% | 47% | – |
| Public Policy Polling (D) | August 2–3, 2017 | 628 (V) | ± 3.8% | 41% | 46% | 13% |
| Public Policy Polling (D) | June 30 – July 1, 2017 | 870 (V) | ± 3.6% | 39% | 53% | 8% |
on whether Cory Gardner deserves to be re-elected
| Poll source | Date(s) administered | Sample size | Margin of error | Yes | No | Other / Undecided |
| Fabrizio Ward/AARP | July 29–31, 2019 | 600 (LV) | ± 4.0% | 32% | 50% | 19% |
with Generic Republican and Generic Democrat
| Poll source | Date(s) administered | Sample size | Margin of error | Generic Republican | Generic Democrat | Other / Undecided |
| YouGov/University of Colorado | October 5–9, 2020 | 800 (LV) | ± 4.64% | 39% | 47% | 14% |
| Climate Nexus | February 15–19, 2020 | 485 (RV) | ± 4.5% | 40% | 48% | 12% |
| Fabrizio Ward/AARP | July 29–31, 2019 | 600 (LV) | ± 4.0% | 42% | 44% | 14% |
with Mike Johnston
| Poll source | Date(s) administered | Sample size | Margin of error | Cory Gardner (R) | Mike Johnston (D) | Other | Undecided |
| Global Strategy Group (D) | August 13–14, 2019 | 617 (LV) | ± 3.9% | 39% | 50% | – | 11% |
| Fabrizio Ward/AARP | July 29–31, 2019 | 600 (LV) | ± 4.0% | 45% | 39% | 2% | 14% |

### Results

The election was not particularly close, with Hickenlooper winning by 9.32%. Hickenlooper's win was expected, as Colorado has moved more toward being a blue state. Key to Hickenlooper's victory was Denver County and its surrounding suburban counties, Adams, Arapahoe, Boulder, and Jefferson, the latter of which had been pivotal to Gardner's victory in 2014. Gardner did well in the typically red El Paso County, home of Colorado Springs. Gardner also did well in many rural areas of the state. However, Hickenlooper's strong performance in heavily populated counties proved too much for Gardner to overcome. Hickenlooper was also likely helped by Joe Biden, who won the state by 13.5%.
Hickenlooper is the first senator from Colorado who was also the Governor of Colorado since Senator Edwin Johnson was elected in 1936. Hickenlooper was sworn in as Senator on January 3, 2021, for a six-year term that expires on January 3, 2027.
United States Senate election in Colorado, 2020 :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | John Hickenlooper | 1,731,114 | 53.50% | +7.24% |
| | Republican | Cory Gardner (incumbent) | 1,429,492 | 44.18% | −4.03% |
| | Libertarian | Raymon Doane | 56,262 | 1.74% | −0.85% |
| | Approval Voting | Daniel Doyle | 9,820 | 0.30% | N/A |
| | Unity | Stephen Evans | 8,971 | 0.28% | −0.04% |
| Total votes | Total votes | Total votes | 3,235,659 | 100.00% | N/A |
| | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican | Democratic gain from Republican |

#### By county

By county :
| County | John Hickenlooper Democratic | John Hickenlooper Democratic | Cory Gardner Republican | Cory Gardner Republican | Raymon Doane Libertarian | Raymon Doane Libertarian | Daniel Doyle Approval Voting | Daniel Doyle Approval Voting | Stephen Evans Unity | Stephen Evans Unity | Margin | Margin | Total votes |
| County | # | % | # | % | # | % | # | % | # | % | # | % | Total votes |
| Adams | 130,409 | 55.33 | 98,341 | 41.72 | 4,916 | 2.09 | 1,071 | 0.45 | 963 | 0.41 | 32,068 | 13.60 | 235,700 |
| Alamosa | 3,734 | 48.45 | 3,800 | 49.31 | 104 | 1.35 | 40 | 0.52 | 29 | 0.38 | -66 | -0.86 | 7,707 |
| Arapahoe | 204,054 | 58.53 | 136,713 | 39.21 | 5,694 | 1.63 | 1,074 | 0.31 | 1,111 | 0.32 | 67,341 | 19.31 | 348,646 |
| Archuleta | 3,591 | 39.82 | 5,225 | 57.93 | 163 | 1.81 | 26 | 0.29 | 14 | 0.16 | -1,634 | -18.12 | 9,019 |
| Baca | 329 | 14.98 | 1,816 | 82.70 | 32 | 1.46 | 12 | 0.55 | 7 | 0.32 | -1,487 | -67.71 | 2,196 |
| Bent | 702 | 31.12 | 1,488 | 65.96 | 33 | 1.46 | 26 | 1.15 | 7 | 0.31 | -786 | -34.84 | 2,256 |
| Boulder | 154,552 | 75.20 | 47,321 | 23.03 | 2,869 | 1.40 | 317 | 0.15 | 457 | 0.22 | 107,231 | 52.18 | 205,516 |
| Broomfield | 27,447 | 59.41 | 17,855 | 38.65 | 712 | 1.54 | 82 | 0.18 | 100 | 0.22 | 9,592 | 20.76 | 46,196 |
| Chaffee | 6,948 | 51.17 | 6,344 | 46.72 | 232 | 1.71 | 32 | 0.24 | 22 | 0.16 | 604 | 4.45 | 13,578 |
| Cheyenne | 119 | 10.58 | 995 | 88.44 | 7 | 0.62 | 2 | 0.18 | 2 | 0.18 | -876 | -77.87 | 1,125 |
| Clear Creek | 3,494 | 53.94 | 2,835 | 43.77 | 121 | 1.87 | 15 | 0.23 | 12 | 0.19 | 659 | 10.17 | 6,477 |
| Conejos | 1,975 | 46.26 | 2,243 | 52.54 | 24 | 0.56 | 18 | 0.42 | 9 | 0.21 | -268 | -6.28 | 4,269 |
| Costilla | 1,313 | 62.91 | 713 | 34.16 | 40 | 1.92 | 12 | 0.57 | 9 | 0.43 | 600 | 28.75 | 2,087 |
| Crowley | 456 | 26.19 | 1,230 | 70.65 | 36 | 2.07 | 12 | 0.69 | 7 | 0.40 | -774 | -44.46 | 1,741 |
| Custer | 1,059 | 29.47 | 2,456 | 68.34 | 62 | 1.73 | 10 | 0.28 | 7 | 0.19 | -1,397 | -38.87 | 3,594 |
| Delta | 5,764 | 29.86 | 13,118 | 67.96 | 308 | 1.60 | 79 | 0.41 | 34 | 0.18 | -7,354 | -38.10 | 19,303 |
| Denver | 305,602 | 77.74 | 80,163 | 20.39 | 4,984 | 1.27 | 963 | 0.24 | 1,376 | 0.35 | 225,439 | 57.35 | 393,088 |
| Dolores | 338 | 23.69 | 1,064 | 74.56 | 17 | 1.19 | 4 | 0.28 | 4 | 0.28 | -726 | -50.88 | 1,427 |
| Douglas | 97,553 | 42.13 | 130,045 | 56.16 | 3,279 | 1.42 | 332 | 0.14 | 350 | 0.15 | -32,492 | -14.03 | 231,559 |
| Eagle | 17,902 | 62.27 | 10,350 | 36.00 | 384 | 1.34 | 53 | 0.18 | 59 | 0.21 | 7,552 | 26.27 | 28,748 |
| El Paso | 152,126 | 40.36 | 212,057 | 56.27 | 9,932 | 2.64 | 1,451 | 0.39 | 1,314 | 0.35 | -59,931 | -15.90 | 376,880 |
| Elbert | 4,257 | 22.46 | 14,340 | 75.64 | 299 | 1.58 | 35 | 0.18 | 26 | 0.14 | -10,083 | -53.19 | 18,957 |
| Fremont | 7,201 | 28.40 | 17,450 | 68.81 | 508 | 2.00 | 129 | 0.51 | 71 | 0.28 | -10,249 | -40.42 | 25,359 |
| Garfield | 14,999 | 48.72 | 15,027 | 48.81 | 598 | 1.94 | 92 | 0.30 | 71 | 0.23 | -28 | -0.09 | 30,787 |
| Gilpin | 2,183 | 52.29 | 1,867 | 44.72 | 99 | 2.37 | 15 | 0.36 | 11 | 0.26 | 316 | 7.57 | 4,175 |
| Grand | 4,579 | 46.36 | 5,075 | 51.38 | 181 | 1.83 | 28 | 0.28 | 15 | 0.15 | -496 | -5.02 | 9,878 |
| Gunnison | 6,922 | 62.13 | 3,978 | 35.71 | 193 | 1.73 | 30 | 0.27 | 18 | 0.16 | 2,944 | 26.42 | 11,141 |
| Hinsdale | 244 | 39.35 | 365 | 58.87 | 9 | 1.45 | 0 | 0.00 | 2 | 0.32 | -121 | -19.52 | 620 |
| Huerfano | 2,077 | 47.52 | 2,160 | 49.42 | 97 | 2.22 | 25 | 0.57 | 12 | 0.27 | -83 | -1.90 | 4,371 |
| Jackson | 164 | 18.92 | 684 | 78.89 | 12 | 1.38 | 5 | 0.58 | 2 | 0.23 | -520 | -59.98 | 867 |
| Jefferson | 210,619 | 55.87 | 158,276 | 41.99 | 6,191 | 1.64 | 1,026 | 0.27 | 849 | 0.23 | 52,343 | 13.88 | 376,961 |
| Kiowa | 93 | 10.45 | 783 | 87.98 | 10 | 1.12 | 3 | 0.34 | 1 | 0.11 | -690 | -77.53 | 890 |
| Kit Carson | 628 | 16.46 | 3,138 | 82.25 | 36 | 0.94 | 8 | 0.21 | 5 | 0.13 | -2,510 | -65.79 | 3,815 |
| La Plata | 19,873 | 56.05 | 14,776 | 41.68 | 632 | 1.78 | 71 | 0.20 | 101 | 0.28 | 5,097 | 14.38 | 35,453 |
| Lake | 2,297 | 58.11 | 1,511 | 38.22 | 109 | 2.76 | 15 | 0.38 | 21 | 0.53 | 786 | 19.88 | 3,953 |
| Larimer | 116,419 | 53.91 | 94,585 | 43.80 | 3,914 | 1.81 | 544 | 0.25 | 471 | 0.22 | 21,834 | 10.11 | 215,933 |
| Las Animas | 3,509 | 44.28 | 4,217 | 53.21 | 130 | 1.64 | 45 | 0.57 | 24 | 0.30 | -708 | -8.93 | 7,925 |
| Lincoln | 434 | 16.46 | 2,141 | 81.22 | 39 | 1.48 | 17 | 0.64 | 5 | 0.19 | -1,707 | -64.76 | 2,636 |
| Logan | 2,117 | 20.20 | 8,167 | 77.92 | 131 | 1.25 | 37 | 0.35 | 29 | 0.28 | -6,050 | -57.72 | 10,481 |
| Mesa | 29,478 | 33.05 | 57,236 | 64.17 | 1,785 | 2.00 | 457 | 0.51 | 244 | 0.27 | -27,758 | -31.12 | 89,200 |
| Mineral | 302 | 39.89 | 437 | 57.73 | 15 | 1.98 | 1 | 0.13 | 2 | 0.26 | -135 | -17.83 | 757 |
| Moffat | 1,120 | 16.45 | 5,544 | 81.41 | 106 | 1.56 | 31 | 0.46 | 9 | 0.13 | -4,424 | -64.96 | 6,810 |
| Montezuma | 5,538 | 36.45 | 9,273 | 61.03 | 272 | 1.79 | 47 | 0.31 | 64 | 0.42 | -3,735 | -24.58 | 15,194 |
| Montrose | 7,321 | 29.45 | 16,978 | 68.31 | 410 | 1.65 | 92 | 0.37 | 55 | 0.22 | -9,657 | -38.85 | 24,856 |
| Morgan | 3,787 | 27.91 | 9,544 | 70.33 | 136 | 1.00 | 69 | 0.51 | 35 | 0.26 | -5,757 | -42.42 | 13,571 |
| Otero | 3,428 | 36.60 | 5,731 | 61.18 | 113 | 1.21 | 67 | 0.72 | 28 | 0.30 | -2,303 | -24.59 | 9,367 |
| Ouray | 2,291 | 57.45 | 1,622 | 40.67 | 68 | 1.71 | 3 | 0.08 | 4 | 0.10 | 669 | 16.77 | 3,988 |
| Park | 4,800 | 39.20 | 7,100 | 57.98 | 281 | 2.29 | 31 | 0.25 | 34 | 0.28 | -2,300 | -18.78 | 12,246 |
| Phillips | 463 | 18.74 | 1,980 | 80.13 | 22 | 0.89 | 6 | 0.24 | 0 | 0.00 | -1,517 | -61.39 | 2,471 |
| Pitkin | 8,761 | 73.88 | 2,935 | 24.75 | 130 | 1.10 | 13 | 0.11 | 20 | 0.17 | 5,826 | 49.13 | 11,859 |
| Prowers | 1,435 | 26.09 | 3,966 | 72.11 | 55 | 1.00 | 26 | 0.47 | 18 | 0.33 | -2,531 | -46.02 | 5,500 |
| Pueblo | 42,791 | 48.93 | 42,098 | 48.14 | 1,720 | 1.97 | 533 | 0.61 | 308 | 0.35 | 693 | 0.79 | 87,450 |
| Rio Blanco | 529 | 14.47 | 3,065 | 83.86 | 46 | 1.26 | 13 | 0.36 | 2 | 0.05 | -2,536 | -69.38 | 3,655 |
| Rio Grande | 2,502 | 39.85 | 3,635 | 57.89 | 84 | 1.34 | 40 | 0.64 | 18 | 0.29 | -1,133 | -18.04 | 6,279 |
| Routt | 10,284 | 61.12 | 6,256 | 37.18 | 223 | 1.33 | 39 | 0.23 | 24 | 0.14 | 4,028 | 23.94 | 16,826 |
| Saguache | 1,887 | 55.84 | 1,405 | 41.58 | 55 | 1.63 | 11 | 0.33 | 21 | 0.62 | 482 | 14.26 | 3,379 |
| San Juan | 328 | 59.64 | 207 | 37.64 | 10 | 1.82 | 2 | 0.36 | 3 | 0.55 | 121 | 22.00 | 550 |
| San Miguel | 3,808 | 74.36 | 1,227 | 23.96 | 76 | 1.48 | 2 | 0.04 | 8 | 0.16 | 2,581 | 50.40 | 5,121 |
| Sedgwick | 320 | 22.11 | 1,103 | 76.23 | 14 | 0.97 | 9 | 0.62 | 1 | 0.07 | -783 | -54.11 | 1,447 |
| Summit | 12,175 | 66.14 | 5,817 | 31.60 | 353 | 1.92 | 25 | 0.14 | 37 | 0.20 | 6,358 | 34.54 | 18,407 |
| Teller | 5,039 | 30.06 | 11,307 | 67.46 | 339 | 2.02 | 54 | 0.32 | 22 | 0.13 | -6,268 | -37.40 | 16,761 |
| Washington | 346 | 11.55 | 2,617 | 87.35 | 22 | 0.73 | 4 | 0.13 | 7 | 0.23 | -2,271 | -75.80 | 2,996 |
| Weld | 63,647 | 38.19 | 99,424 | 59.65 | 2,761 | 1.66 | 470 | 0.28 | 376 | 0.23 | -35,777 | -21.46 | 166,678 |
| Yuma | 652 | 13.10 | 4,273 | 85.85 | 29 | 0.58 | 19 | 0.38 | 4 | 0.08 | -3,621 | -72.75 | 4,977 |
| Totals | 1,731,114 | 53.50 | 1,429,492 | 44.18 | 56,262 | 1.74 | 9,820 | 0.30 | 8,971 | 0.28 | 301,622 | 9.32 | 3,235,659 |

#### By congressional district

Hickenlooper won four of seven congressional districts.
| District | Gardner | Hickenlooper | Representative |
| 1st | 24% | 74% | Diana DeGette |
| 2nd | 36% | 62% | Joe Neguse |
| 3rd | 52% | 45% | Scott Tipton |
| 3rd | 52% | 45% | Lauren Boebert |
| 4th | 59% | 39% | Ken Buck |
| 5th | 57% | 40% | Doug Lamborn |
| 6th | 42% | 56% | Jason Crow |
| 7th | 39% | 58% | Ed Perlmutter |