Thomas Massie vs. Trump-Backed Ed Gallrein: Final Polls and Odds
Representative Thomas Massie faces a close race against Trump-backed challenger Ed Gallrein in the Republican primary for Kentucky's 4th Congressional District on Tuesday, according to recent polls and prediction markets.
Massie, one of the most conservative members of Congress, has clashed with President Trump over foreign policy and the Department of Justice's handling of the Epstein files. He has also been the subject of hush money allegations by a former congressional aide.
The president's support for Gallrein over Massie in the primary highlights a deeper struggle over the future direction of the Republican Party.
The primary is also a test for Trump's popularity, pitting him against a well-known incumbent in a solidly conservative district. Historically, Trump's endorsements carry significant influence over the GOP electorate, but the Kentucky primary will be the latest gauge into whether that influence has faded as his national approval rating waned.
Thomas Massie vs. Ed Gallrein: What Polls Show
Polls suggest Massie and Gallrein are divided by only a razor-thin margin. Massie led initial polling of the primary back in April, but the latest information suggest the race has tightened in its final stretch, with both candidates leading recent surveys.
The latest poll from GrayHouse gave Gallrein 51 percent of the vote, compared with Massie's 44 percent. It surveyed 435 likely voters from May 16-17. Five percent of respondents in the poll were still unsure of for whom they would vote.
Gallrein also led a poll from SoCal strategies, which gave him 49 percent compared to Massie's 42 percent. Nine percent were unsure of who they would support, and those undecided voters will be critical to the final outcome of the race. It surveyed 450 likely Republican voters from May 15-16.
Trump's endorsement has been critical to Gallrein's surge, Assistant Professor of Political Science at the University of Kentucky D. Stephen Voss, told Newsweek.
“The Trump endorsement gave Gallrein’s sleepy campaign a burst of attention it badly needed,” he said. “It also gave low-information Trump supporters the information they needed to identify the most Trump-aligned candidate. Gallrein is reaping the dividends of Trump’s active support.”
Turnout remains an open question heading into the primary, he said, noting that Massie, who relies on younger voters, could benefit from higher turnout. At the same time, low-propensity Trump voters motivated by his endorsement could help Gallrein.
Trump's influence in the 4th District is likely "to be lower" than in other places, he said, noting it is highly urbanized due to its proximity to Louisville and Cincinnati.
The 4th District is known for having an independent streak and is located in Northern Kentucky. It is comprised of Cincinnati suburbs and more rural areas in the region
“The voters in this region, which looks to the Midwest rather than the South for its political flavors, are more polarized than found elsewhere in Kentucky, with a solid base of Democrats counteracting Republican voters who tend to be more ideological than those elsewhere in Kentucky,” Voss said. “It’s relatively safe territory for a member of Congress resisting the Trump White House, which is why Massie is still in the game.”
A Big Data poll pointed to an even closer race. Gallrein held an initial lead, gaining the support of 43.7 percent of respondents compared with Massie's 43 percent. However, when undecided voters were pushed, Massie led with 50.2 percent, while 49.8 percent said they would support Gallrein. It surveyed 555 likely voters from May 14-16.
Gallrein led the latest poll from Quantus Insights, which found that 53 percent of respondents planned to support him, compared with 45 percent who planned to vote for Massie. Only 2 percent were undecided. It surveyed 908 likely voters May 11-12 and had a margin of error of plus or minus 3.3 percentage points.
The pollster noted that Massie holds a “durable base” but that Gallrein still holds a lead on both the initial ballot and when leaners are pushed.
“In a nationalized Republican primary shaped by Trump's endorsement, outside spending, and Massie's independent brand, Gallrein enters the final stretch with the advantage,” the pollster wrote.
An earlier Quantus Insights poll gave Massie a lead but found a larger number of undecided voters. It found Massie with 47 percent support to Gallrein's 38 percent, while 14 percent said they were undecided. It surveyed 438 likely Republican primary voters from April 6-7 and had a margin of error of plus or minus 4.4 percentage points.
If Massie loses, he would become the second incumbent Republican to lose renomination to a Trump-backed challenger in recent days, as Louisiana Senator Bill Cassidy failed to advance to the runoff in the state's primary over the weekend. Trump's endorsements over the past few years have taken out numerous incumbents and have helped reshape the GOP in his image.
Ed Gallrein’s Last Minute Surge in Prediction Markets
In the final stretch of the campaign, Gallrein surged past Massie in prediction markets. On Monday, Gallrein had a 63 percent chance of winning on both Kalshi and Polymarket, a signal that he has built up last-minute momentum over the incumbent Republican.
Prediction markets allow traders to buy and sell contracts tied to political outcomes and current events, aggregating real‑money wagers into probability estimates.
Prices fluctuate as traders react to polling, fundraising, candidate developments and broader political trends. They measure trader sentiment at a given moment but do not always accurately predict the future.
Whoever wins the primary will be the significant favorite against a Democrat in the general election. The district is solidly Republican, backing Trump by more than 35 points in the 2024 presidential race.
Republican Politicians Take Sides in Kentucky Race
Prominent Republicans have taken sides in the Massie-Trump feud.
GOP members of Congress including Representatives Lauren Boebert and Victoria Spartz have headed to Kentucky in recent days to campaign with Massie. Meanwhile, Defense Secretary Pete Hegseth campaigned with Gallrein.
Trump criticized Boebert, also viewed among the most conservative, MAGA-aligned members of Congress, over her support for Massie.
“”Is anyone interested in running against Weak Minded Lauren Boebert in Colorado's Fourth Congressional District,” Trump wrote to Truth Social over the weekend. “Boebert is campaigning for the Worst ‘Republican’ Congressman in the History of our Country, Thomas Massie, of the Great Commonwealth of Kentucky, and anybody who can be that dumb deserves a good Primary fight! Even though I long ago endorsed Boebert, if the right person came along, it would be my Honor to withdraw that Endorsement, and endorse a good and proper alternative. Just let me know, or announce your Candidacy, and I will be there for you!”
Former Representative Marjorie Taylor Greene, another former Trump ally who has distanced herself from the president, has also weighed in.
“The only record Ed Gallrein has is being too timid, too weak, and too afraid, to debate Thomas Massie and refused to show up at campaign debates in the district he's trying to get elected in!!!” she wrote in a May 4 post to X.
Trump and Massie’s Fallout Explained
Trump has long had a rocky relationship with Massie, whose libertarian-leaning principles have not always meshed well with Trump's MAGA style of politics. Their first major clash came in March 2020 after Massie voted against the Save Our Workers Bill, a $2 trillion COVID-19 relief package. Trump called him a “third rate Grandstander,” urging the GOP to “throw Massie out” of their party in a post to X, then known as Twitter.
By the 2024 presidential race, their relationship had improved, with Massie endorsing Trump's campaign.
He said Trump would “put Americans first by securing our liberties at home and preventing needless wars abroad” and “make America Healthy Again by empowering small farmers and taking on special interests that have corrupted our healthcare system” in a statement widely reported in October 2024.
However, Massie has voted against parts of Trump's agenda, including the One Big Beautiful Bill Act, which Congress passed last year. He has also opposed Trump's foreign policy actions, including military strikes on Iran and supported a War Powers Resolution aimed at curbing the president’s ability to declare war on Iran.
The Iran war threatens to be a challenge for Republicans this year, as polls show it is unpopular. The confict has sent global oil prices surging, leading to higher gas prices for Americans, and doing little to quell concerns about inflation and the high cost of living.
Massie has also led an effort, alongside Democratic Representative Ro Khanna of California, to force the Justice Department to release the files related to Jeffrey Epstein, the sex offender and disgraced financier who died by suicide in a New York City federal jail in 2019 while awaiting trial on charges of sex trafficking.
The Epstein files and Iran war were major turning points in the relationship between Trump and Massie.
The president has repeatedly attacked Massie on social media.
“I predict that ‘Representative' Thomas Massie will go down as the WORST Republican Congressman in the long and fabled history of the United States Congress, even worse than Crazy Liz [Cheney], Cryin' Adam Kinzinger, and Marjorie “Traitor” Brown (Remember, Green turns to Brown under stress!). They are all misfits and losers, but Massie, who is running against a great American Patriot in the Kentucky Primary, will hopefully lose BIG,” Trump wrote on March 11.
Trump has been a vocal proponent of Gallrein, a farmer and veteran who has garnered support from other prominent Kentucky Republicans such as Representative Andy Barr. Senator Rand Paul is backing Massie.
Thomas Massie Hush Money Claims Explained
Last week, Cynthia West, a former congressional aide, alleged that Massie tried to bribe her with undeclared income. Massie has denied those allegations and described them as “unsubstantiated.”
West said Massie secured her a job in Congress in Spartz's office after the pair began a romantic relationship. West added that she ended the relationship after Massie began to engage in behavior she was not comfortable with.
West alleged that Massie offered her $5,000 after she said she would file a wrongful termination complaint against Spartz. West said that Spartz had fostered a toxic working environment.
She added that she had declined this money, as well as a $60,000 settlement payment for “retaliatory discharge,” which would have required her to sign a nondisclosure agreement.
In a statement to Newsweek on May 13, Massie said: “It's sad that a week before this election people are making false and unsubstantiated allegations about me in an obvious attempt to influence the outcome of this election.”
Spartz wrote in a statement shared to X that West was not fired. Rather, her office chose not to extend her temporary 90-day employment because of “concerning conduct by Ms. West.” She added that the complaint against her office came a few months later, and that she had denied this and refused to settle.
She defended Massie in her statement and wrote that she considers him to be “one of the strongest supporters of women in Congress and a defender of women's rights among her GOP colleagues.”
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This story was originally published May 19, 2026 at 6:40 AM.