2020 United States Senate election in Montana

The 2020 United States Senate election in Montana was held on November 3, 2020, to elect a member of the United States Senate to represent the State of Montana. It was held concurrently with the 2020 U.S. presidential election, as well as other elections to the United States Senate in other states, elections to the United States House of Representatives, and various state and local elections. The primaries for both the Democratic and Republican nominations took place on June 2, 2020. Incumbent senator Steve Daines won the Republican primary, while Montana Gov. Steve Bullock won the Democratic primary.

Originally, this seat was projected to be a safe Republican hold. However, Bullock entered the race on the last day to file, shifting the dynamics of the contest dramatically; many political pundits then considered it a competitive race and a potential pickup for Democrats. One poll showed Bullock leading by seven points. Democrats outspent Republicans $82 million to $63 million on this race; it was one of the most expensive Senate races in the 2020 cycle. On Election Day, Daines prevailed by a relatively comfortable 10-point margin following a trend of Republican Senate candidates outperforming expectations.

This election marked the first time since 2000 where Montana voted for a Republican governor, president, and senator all on the same ballot. As the Green Party was removed from the ballot and both Libertarian nominees withdrew, this was the first time since 1988 that there were no third-party candidates running for either United States House of Representatives or United States Senate in Montana. This was the first time ever that an incumbent Republican senator was re-elected to this seat.

Nominee

 * Steve Daines, incumbent U.S. senator

Eliminated in primary

 * John Driscoll, former Democratic Speaker of the Montana House of Representatives (1977–1979)
 * Daniel Larson, hardware store manager

Results
[[File:Montana U.S. Senate Republican primary, 2020.svg|thumb|Results by county {{legend|#e27f7f|Daines}}

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Democratic primary
Following Steve Bullock's entry shortly before the March 9 filing deadline, several Democrats dropped from the race.

Nominee

 * Steve Bullock, incumbent governor of Montana and former candidate for President of the United States in 2020

Eliminated in primary

 * John Mues, nuclear engineer and U.S. Navy veteran

Withdrawn

 * Jack Ballard, former professor at Montana State University Billings (endorsed Bullock)
 * Wilmot Collins, mayor of Helena (endorsed Bullock)
 * Mike Knoles, mathematician, physicist, and data analyst (endorsed Bullock) (remained on ballot)
 * Cora Neumann, public health expert and founder of the Global First Ladies Alliance (endorsed Bullock)
 * Josh Seckinger, fishing guide (endorsed Bullock)

Declined

 * 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 (running for Montana's at-large congressional district)

Results
[[File:Montana U.S. Senate Democratic primary, 2020.svg|thumb|Results by county {{legend|#7996e2|Bullock}}

{{legend|#3933e5|80–90%}}

{{legend|#0d0596|90–100%}} ]]

Libertarian Party
After Susan Geise officially withdrew, the Montana Libertarian Party could name a replacement candidate for the general election. However, during a meeting to select a replacement candidate, a majority of party officials selected not to have a replacement candidate, with "none of the above" winning the most votes.

Withdrawn

 * Eric Fulton, Republican candidate for District 65 of the Montana House of Representatives in 2014
 * Susan Geise, Lewis and Clark County commissioner and former chair of the Montana Republican Party

Disqualified

 * Wendie Fredrickson, former audit reviewer for Montana State Department of Public Health and Human Services

Eliminated in primary

 * Dennis Daneke, retired college professor

Polling

 * Graphical summary

Aggregate polls

University of Montana polls did not account for certain presumed withdrawals of major party candidates after their primaries in the following polls.
 * Steve Daines vs Steve Bullock, Wilmot Collins, Mike Knoles, Cora Neumann, and John Mues


 * Steve Daines vs Jack Ballard, Wilmot Collins, and John Mues

Results

 * Counties that flipped from Republican to Democratic
 * Gallatin (largest municipality: Bozeman)
 * Lewis and Clark (largest municipality: Helena)
 * Roosevelt (largest municipality: Wolf Point)