Former President Donald Trump is backing a challenger against Representative Thomas Massie in Tuesday’s Kentucky Republican primary, intensifying his campaign to remove critics from within the party.
The primary battle — which has become the costliest U.S. House primary race in American history — will once more examine Trump’s influence over Republicans following his successful efforts to oust another major critic, Senator Bill Cassidy of Louisiana, and secure wins against opposing incumbents in Indiana.
Should Massie be defeated, it would strengthen Trump’s control over his core base within the party before November’s midterm elections and signal to other Republicans the political price of opposing him.
Massie drew Trump’s anger by spearheading efforts to make public documents related to deceased sex offender Jeffrey Epstein, along with his opposition to the Iran war.
In a Sunday message on Truth Social, Trump labeled Massie “the worst and most unreliable Republican Congressman in the history of our Country,” encouraging Kentuckians to “vote the bum out.”
The race between libertarian-minded Massie and Trump-endorsed Ed Gallrein, a former Navy SEAL, has generated over $30 million in advertising expenditures, based on data from tracking company AdImpact.
Additional primaries are taking place Tuesday throughout Alabama, Georgia, Idaho, Kentucky, Oregon, and Pennsylvania, helping determine the landscape for November’s elections, when Democrats seek to gain House control and possibly the Senate despite Republican advantages from national redistricting efforts.
However, the battle for Massie’s seat — covering Louisville’s suburban areas, Kentucky’s portion of the Cincinnati metropolitan region, and eastern rural counties bordering Appalachia — is emerging as Tuesday’s featured competition.
Stephen Voss, a political science professor at the University of Kentucky, described the race as “a battle between ideological purity and party unity” in a conservative area where Trump enjoys massive support but Massie’s anti-establishment libertarian philosophy also has strong roots.
“A Massie victory will be seen as a sign that it’s okay for Republicans to go up against Donald Trump if they do so with a clear vision,” Voss said. A Massie loss would “strike fear in the hearts of other Republicans who want to keep their jobs as elected officials.”
Supporting the president’s revenge efforts, Cassidy was defeated in Louisiana’s primary on Saturday after being targeted for his 2021 vote to convict Trump on impeachment charges. He becomes the first sitting U.S. senator to lose renomination since 2012.
Cassidy’s loss came after the president’s successful campaign for payback against Indiana Republican state senators who opposed his redistricting efforts, with at least five incumbents defeated in May 5 primaries by Trump-endorsed candidates.
Massie’s votes opposing U.S. aid to Israel have triggered an influx of funding from pro-Israel organizations into the contest, with the Republican Jewish Coalition and the American Israel Public Affairs Committee investing heavily to defeat him. Additional millions have flowed from a Trump-affiliated super PAC supported by pro-Israel contributors including hedge fund manager Paul Singer and casino magnate Miriam Adelson.
By comparison, Massie reports his average contribution is below $94, coming from approximately 33,000 donors across the nation.
Total expenditures have hit $32 million, exceeding the $25 million spent in a 2024 effort to defeat Democratic Representative Jamaal Bowman in New York, according to AdImpact.
Public surveys indicate the Massie-Gallrein contest remains tight. A May 11 to 12 Quantus Insights poll of 908 voters showed 48.3% supporting Gallrein and 43.1% for Massie, while a separate Big Data Poll survey of 518 registered Republicans released Friday placed Massie ahead by 1 percentage point.
Both surveys show a clear generational split, with younger voters under 45 strongly supporting Massie and Gallrein winning among older voters, particularly those over 65.
Gallrein has portrayed himself as a dependable team member who would consistently support Trump. In recent days, Massie has emphasized that he still votes with Trump approximately 90% of the time, even as his independent positions highlight the danger of alienating Kentucky voters devoted to a president who easily carried the state in 2024 with 64.5% of the vote.
“This really is a Trump versus Massie race. It has come down to a pick-a-side moment,” said Shane Noem, chairman of the Republican Party in Kenton County, which is located in the district.
Tuesday’s other races could also provide insights into the Republican Party’s future direction heading into November.
In Georgia, Republicans will select a candidate to challenge Democratic Senator Jon Ossoff in November while choosing from a large primary field for the replacement of term-limited Governor Brian Kemp. In that contest, Trump-endorsed Lieutenant Governor Burt Jones is among the top candidates seeking to face a Democratic field headed by former Atlanta Mayor Keisha Lance Bottoms.
In Kentucky, Republicans will vote for their candidate to succeed longtime Senate leader Mitch McConnell, with U.S. Representative Andy Barr, who received Trump’s endorsement, and Attorney General Daniel Cameron as the leading candidates.
