The 2024 United States Senate election in Arizona was held on November 5, 2024, to elect a member of the United States Senate to represent the state of Arizona. Democratic Congressman Ruben Gallego won his first term in office, defeating Republican former news anchor Kari Lake. He succeeded independent incumbent Kyrsten Sinema, who did not seek a second term.
Sinema, who was elected as a Democrat, was considered vulnerable to a primary challenge due to frequently opposing her party's legislative agenda. After preparing a re-election bid as an independent, Sinema announced she would retire from the Senate. Gallego ran unopposed in the Democratic primary. Lake, the Republican nominee in the 2022 Arizona gubernatorial election, won her party's nomination with 55% of the vote against Pinal County sheriff Mark Lamb. The election was considered among the most competitive Senate races in 2024. Most polls and ratings had Gallego as the favorite to win. Gallego defeated Lake by 2.41 percentage points, a closer race than polls had projected for most of the campaign. Republican presidential candidate Donald Trump's wider-than-expected victory in the state likely contributed to this, but there was also a significant amount of ticket splitting between the presidential and senatorial races.
Gallego outperformed Kamala Harris by the fourth-largest margin among Democratic Senate candidates in 2024, and the largest margin for a non-incumbent. Gallego particularly benefitted from ticket splitting among Hispanics, who according to exit polls gave Gallego 60% of their votes, compared to 54% for Harris. Specifically, Gallego received 93,475 more votes than Harris, while Lake received 174,481 fewer votes than Donald Trump. This election marked the fourth consecutive election cycle in which Democrats won a Senate election in Arizona.
This was the first time that Arizona voted for candidates of different political parties for U.S. senator and president since Democrat Dennis DeConcini was reelected as Republican George H. W. Bush carried the state in 1988. Gallego also became the first Latino elected to the Senate from Arizona, a state with a large Latino population. This was the first time since 2006 that any candidate won a majority of the vote in this seat.
Similarly to the 2022 Arizona gubernatorial election, Lake refused to concede defeat.
Background Arizona was once considered a Republican stronghold, but has become a critical swing state. Both parties have seen success in the state in recent years. As of May 2024, Democrats control the governorship, most other statewide offices, and both U.S. Senate seats, while Republicans control both houses of the Arizona State Legislature and a 6–3 majority of Arizona's U.S. House delegation. Republican presidential candidate Donald Trump won Arizona by 3.5% in 2016, while Democratic presidential candidate Joe Biden prevailed by 0.3% in 2020.
Democratic primary Prior to her departure from the Democratic Party, Sinema was considered highly vulnerable to a primary challenge due to her opposition to several parts of the Democratic Party's legislative agenda. Prospective polling showed Sinema trailing all of her potential challengers by wide margins, with U.S. Representative Ruben Gallego being viewed by numerous political analysts as the frontrunner to challenge her. On January 22, 2022, the Arizona Democratic Party voted overwhelmingly to censure Sinema for a second time for voting against a carve-out to the Senate filibuster rule in a Democratic-led effort to pass the John Lewis Voting Rights Act. Sinema did not support the Inflation Reduction Act until after Democratic leaders agreed to remove a provision closing the so-called carried interest tax loophole, the closure of which would have raised taxes on hedge fund owners and investment managers. This action renewed calls from Democrats for Sinema to face a primary opponent in her next election.
Sinema left the Democratic Party in December 2022 and registered as an independent, while continuing to be counted as part of the Senate Democratic Caucus.
Candidates Nominee Ruben Gallego, U.S. representative for (2015–2025)
Declined Kate Gallego, mayor of Phoenix (2019–present) (endorsed Ruben Gallego, her ex-husband) Greg Stanton, U.S. representative for (2019–present) and former mayor of Phoenix (2012–2018) (ran for re-election)
Endorsements
Polling
Ruben Gallego vs. Alexander Keller Poll source Date(s)administered Samplesize Marginof error RubenGallego AlexanderKeller Other UndecidedEmerson CollegeAugust 2–4, 2023571 (LV)–48%6%6%40% Ruben Gallego vs. Kate Gallego vs. Kathy Hoffman vs. Regina Romero vs. Kyrsten Sinema vs. Greg Stanton
Poll source Date(s)administered Samplesize Marginof error KateGallego RubenGallego KathyHoffman ReginaRomero KyrstenSinema GregStanton UndecidedData for Progress (D)January 21–24, 2022673 (LV)± 4.0%–74%––16%–10%–66%––17%–17%Noble Predictive InsightsNovember 1–8, 2021229 (RV)± 6.5%–47%––24%–29%––44%–24%–32%––––25%47%28%Data for Progress (D)October 8–10, 2021467 (LV)± 5.0%9%23%–9%19%13%26%60%–––25%–15%–62%––23%–15%–––55%26%–19%––––24%59%17%
Results
Republican primary Candidates Nominee Kari Lake, former KSAZ-TV news anchor and nominee for governor of Arizona in 2022
Eliminated in primary Mark Lamb, Pinal County sheriff (2017–2024) Elizabeth Jean Reye, neuroscientist
Declined Juan Ciscomani, U.S. representative for (2023–present) Doug Ducey, governor of Arizona (2015–2023) Abraham Hamadeh, former prosecutor in the Maricopa County attorney's office and nominee for Arizona attorney general in 2022 (ran for U.S. House, endorsed Lake) Blake Masters, venture capitalist and nominee for U.S. Senate in 2022 (ran for U.S. House, endorsed Lake) Karrin Taylor Robson, former member of the Arizona Board of Regents (2017–2021) and candidate for governor of Arizona in 2022 (endorsed Lake) Kelli Ward, former state senator from the 5th district (2013–2015), former chair of the Arizona Republican Party (2019–2023), and candidate for U.S. Senate in 2016 and 2018
Endorsements
Fundraising Campaign finance reports as of July 10, 2024CandidateRaisedSpentCash on handKari Lake$10,352,741$8,290,053$2,062,687Mark Lamb$2,059,130$1,795,730$263,400Source: Federal Election Commission
Polling Poll source Date(s)administered Samplesize Marginof error KariLake MarkLamb Other UndecidedNoble Predictive InsightsJuly 22–23, 2024438 (LV)± 4.7%49%38%7%2%Noble Predictive InsightsMay 7–14, 2024364 (RV)± 5.1%46%21%9%25%Rasmussen Reports (R)February 21–26, 2024469 (LV)± 3.0%55%26%7%12%Noble Predictive InsightsFebruary 6–13, 2024384 (RV)± 5.0%54%21%9%17%
Poll source Date(s)administered Samplesize Marginof error AbeHamadeh KariLake MarkLamb JimLamon BlakeMasters Robson BrianWright Other UndecidedNoble Predictive InsightsOctober 25–31, 20231,010 (RV)± 3.1%–40%14%–10%–4%–33%Emerson CollegeAugust 2–4, 2023667 (LV)± 3.7%–42%11%2%7%–2%–28%J.L. PartnersApril 10–12, 2023550 (LV)± 4.2%4%38%8%3%7%10%–2%29%
Results
Green primary The Arizona Green Party endorsed the write-in campaign of Quintana and was "actively opposed" to Hernandez and Norton's campaigns. A press release on the national Green Party's website stated that party leaders alleged that Norton was a plant for the Democratic Party, and that Hernandez was a plant for the Republican Party.
Candidates Nominee Eduardo Heredia Quintana (write-in), chair of the Pima County Green Party
Eliminated in primary Arturo Hernandez Mike Norton, nonprofit executive
Endorsements
Fundraising Campaign finance reports as of June 30, 2024CandidateRaisedSpentCash on handMike Norton$84,401$76,692$7,708Source: Federal Election Commission
Results
Independents Candidates Declined Kyrsten Sinema, incumbent U.S. senator (2019–2025)
Endorsements
Fundraising Italics indicate a declined candidate Campaign finance reports as of March 31, 2024CandidateRaisedSpentCash on handKyrsten Sinema (I)$17,047,387$7,065,565$10,153,343Source: Federal Election Commission
General election Predictions SourceRankingAs of Elections Daily October 9, 2024 CNalysis October 15, 2024 RealClearPolitics October 3, 2024 Sabato's Crystal Ball September 6, 2024 Inside Elections October 10, 2024 The Cook Political Report September 12, 2024 Decision Desk HQ/The Hill September 20, 2024 Split Ticket October 23, 2024 538 October 23, 2024
Campaign strategy Gallego's campaign emphasized his military service record, highlighting his deployment to Iraq as a Marine Corps infantryman. His campaign positioned his military credentials as evidence of his ability to work across party lines and appeal to independent voters. Lake's campaign focused on her alignment with Trump, and emphasized border security and election integrity issues.
Post-primary endorsements
Debates + 2024 Arizona U.S. Senate election debate Date Host Moderators Link Democratic RepublicanKey: Participant Absent Not invited Invited Withdrawn Gallego Lake1 October 10, 2024 Clean Elections Steve GoldsteinNohelani Graf
Post-primary fundraising Campaign finance reports as of October 16, 2024CandidateRaisedSpentCash on handRuben Gallego (D)$56,843,786$55,360,823$2,759,538Kari Lake (R)$21,396,539$18,239,291$3,157,247Source: Federal Election Commission
Polling Aggregate polls Source of pollaggregationDatesadministeredDatesupdated RubenGallego (D) KariLake (R) UndecidedMarginFiveThirtyEightthrough November 4, 2024November 4, 202449.4%45.3%5.3%Gallego +4.1%RealClearPoliticsOctober 20 – November 4, 2024November 4, 202448.8%45.6%5.4%Gallego +3.2%270toWinOctober 22 – November 4, 2024November 4, 202449.5%44.3%6.2%Gallego +5.2%TheHill/DDHQthrough November 4, 2024November 4, 202449.3%45.8%4.9%Gallego +3.5%Average49.3%45.3%5.4%Gallego +4.0%