2020 Montana gubernatorial election
The 2020 Montana gubernatorial election was held on November 3, 2020, to elect the next governor of Montana, concurrently with the U.S. presidential election, as well as elections to the U.S. Senate and the House of Representatives and various state and local elections. It resulted in voters selecting Greg Gianforte over Mike Cooney. Incumbent Democratic governor Steve Bullock was term-limited and could not seek a third consecutive term in office, and he ran unsuccessfully for Montana's Class II Senate seat.
Bullock's lieutenant governor, Mike Cooney, was the Democratic nominee, while the Republican nominee was Montana's at-large representative Greg Gianforte, who won the election, making him the first Republican governor of Montana since Judy Martz left office in 2005. This was the only gubernatorial seat to change partisan control in the 2020 elections. This election marked the first time since the 1920s that Republicans controlled all state constitutional offices and a majority of the legislature.
Democratic primary
Candidates
Nominee
- Mike Cooney, lieutenant governor of Montana and former Secretary of State of Montana and candidate in 2000
- * Running mate: Casey Schreiner, minority leader of the Montana House of Representatives
Eliminated in primary
- Whitney Williams, businesswoman and daughter of former U.S. Representative Pat Williams
- * Running mate: Buzz Mattelin, farmer and president of the National Barley Growers Association
Withdrawn
- Reilly Neill, former state representative
- Casey Schreiner, minority leader of the Montana House of Representatives
Declined
- Ryan Busse, businessman
- Wilmot Collins, mayor of Helena and former 2020 candidate for the U.S. Senate
- John Heenan, attorney and candidate for Montana's at-large congressional district in 2018
- Michael Punke, writer and former U.S. ambassador to the World Trade Organization
- Brian Schweitzer, former governor of Montana
- Kathleen Williams, former state representative and nominee for Montana's at-large congressional district in 2018
Polling
Polls with a sample size of <100 have their sample size entries marked in red to indicate a lack of reliability.| Poll source | Date administered | Sample size | Margin of error | Mike Cooney | Reilly Neill | Casey Schreiner | Whitney Williams | Other / Undecided |
| Montana State University Billings | October 7–16, 2019 | 40 | – | 19% | 2% | 6% | 11% | 62% |
Republican primary
Candidates
Nominee
- Greg Gianforte, incumbent U.S. representative for Montana's at-large congressional district and nominee for governor of Montana in 2016
Eliminated in primary
- Tim Fox, Attorney General of Montana
- Albert Olszewski, state senator and candidate for U.S. Senate in 2018
Withdrawn
- Gary Perry, former state senator
- Corey Stapleton, Secretary of State of Montana, candidate for governor of Montana in 2012 and candidate for the U.S. House in 2014
- Pete Ziehli
Declined
- Matt Rosendale, Montana State Auditor and nominee for the U.S. Senate in 2018
- Ryan Zinke, former United States Secretary of Interior and former U.S. representative for Montana's at-large congressional district
Polling
Polls with a sample size of <100 have their sample size entries marked in red to indicate a lack of reliability.| Poll source | Date administered | Sample size | Margin of error | Tim Fox | Greg Gianforte | Albert Olszewski | Other / Undecided |
| Montana State University Billings | October 7–16, 2019 | 99 | – | 25% | 33% | 9% | 32% |
| Gravis Marketing | August 28–30, 2019 | 433 | ± 4.7% | 29% | 56% | 15% | – |
| Moore Information | July 7–10, 2019 | 400 | ± 5.0% | 17% | 56% | 5% | 23% |
Other candidates
Libertarian Party
Nominee
- Lyman Bishop, founder and CEO of Hoplite Armor
- *Running mate: John Nesper
Withdrawn
Green Party
Disqualified
- Robert Barb
- *Running mate: Joshua Thomas
General election
Polling
| Poll source | Date administered | Sample size | Margin of error | Mike Cooney | Greg Gianforte | Other / Undecided |
| Change Research | October 29 – November 2, 2020 | 920 | ± 3.5% | 44% | 48% | 6% |
| Montana State University Billings | October 19–24, 2020 | 546 | ± 4.2% | 45% | 45% | 11% |
| Siena College/NYT Upshot | October 18–20, 2020 | 758 | ± 4.4% | 44% | 48% | 8% |
| Strategies 360/NBCMT | October 15–20, 2020 | 500 | ± 4.4% | 41% | 48% | 11% |
| RMG Research/PoliticalIQ | October 15–18, 2020 | 800 | ± 3.5% | 45% | 48% | 5% |
| RMG Research/PoliticalIQ | October 15–18, 2020 | 800 | ± 3.5% | 47% | 46% | 5% |
| RMG Research/PoliticalIQ | October 15–18, 2020 | 800 | ± 3.5% | 43% | 50% | 5% |
| Emerson College | October 4–7, 2020 | 500 | ± 3.7% | 41% | 54% | 5% |
| Montana State University Bozeman | September 14 – October 2, 2020 | 1,605 | ± 3.9% | 42% | 47% | 11% |
| Siena College/NYT Upshot | September 14–16, 2020 | 625 | ± 4.8% | 39% | 45% | 16% |
| Global Strategy Group | August 18–23, 2020 | 600 | – | 46% | 47% | – |
| Emerson College | July 31 – August 2, 2020 | 584 | ± 4.0% | 41% | 50% | 10% |
| Civiqs/Daily Kos | July 11–13, 2020 | 873 | ± 4.2% | 44% | 47% | 9% |
| Public Policy Polling | July 9–10, 2020 | 1,224 | ± 2.8% | 42% | 46% | 12% |
| University of Montana | June 17–26, 2020 | 517 | ± 4.3% | 36% | 46% | 18% |
| The Progress Campaign | April 14–21, 2020 | 1,712 | ± 4.6% | 41% | 43% | 16% |
with Mike Cooney, Tim Fox, Greg Gianforte, Albert Olszewski, Ron Vandevender and Whitney Williams
| Poll source | Date administered | Sample size | Margin of error | Democratic candidates | Republican candidates | Ron Vandevender |
| University of Montana | February 12–22, 2020 | 498 | ± 4.4% | 35.1% | 61.7% | 1.3% |
with Mike Cooney, Tim Fox, Greg Gianforte, Reilly Neill, Albert Olszewski, Gary Perry, Casey Schreiner and Whitney Williams
| Poll source | Date administered | Sample size | Margin of error | Democratic candidates | Republican candidates |
| University of Montana | September 26 – October 3, 2019 | 303 | ± 5.6% | 40% | 60.1% |
with Tim Fox, Matt Rosendale, Corey Stapleton, Kathleen Williams and Whitney Williams
| Poll source | Date administered | Sample size | Margin of error | Democratic candidates | Republican candidates | Other / Undecided |
| University of Montana | February 21 – March 1, 2019 | 293 | ± 5.7% | 32.4% | 48.4% | 19.2% |