President Donald Trump and Kentucky Republicans have coalesced around challenger Ed Gallrein in a bid to defeat incumbent Rep. Thomas Massie in Kentucky's 4th Congressional District Republican primary on May 19.

Trump, who endorsed Gallrein before the former Navy SEAL entered the race last October, headlined a rally in Hebron on March 11, where he labeled Massie a "disaster for our party" and urged voters to remove him from office. A super PAC formed by Trump's allies has poured more than $3 million into ads attacking Massie over his opposition to Trump's immigration policies and tax cuts, while pro-Israel groups have added millions more. Total ad spending in the race has exceeded $16 million, with over $10 million aimed at Massie.

Local Republican leaders, long frustrated with Massie, have joined the effort. Former Covington commissioner Steve Frank and ex-state Sen. Adam Koenig have backed Gallrein, citing Massie's votes against district priorities like bridge funding and complaints about poor constituent services, such as delays in Global Entry renewals. Business interests in the district have also bristled at Massie's independent streak.

Gallrein, a fifth-generation farmer from Shelby County and 30-year military veteran who also served as an Army Ranger, emphasizes alignment with Trump's agenda. He pledges to cut taxes and spending, secure the border, and protect gun rights. Gallrein lost a 2024 state Senate primary but gained Trump's early nod for this congressional bid.

Massie, a seven-term congressman first elected in a 2012 special election, defends his record as principled conservatism. The MIT-educated farmer and former Lewis County judge executive has bucked party leadership on spending bills, foreign aid, including Trump's Iran strikes, and government surveillance. He holds endorsements from Sen. Rand Paul and the National Association for Gun Rights. Massie recently stated, “I’m actually glad everybody’s in with both feet, and the chips are all pushed in... For me, it means they tried me, and they couldn’t do it.”

Recent polls show Massie holding a lead. A Quantus Insights survey from April 6-7 found Massie at 47% to Gallrein's 38% among 438 likely voters, with 14% undecided. A Big Data Poll from April 3-7 had Massie ahead 52% to 48%. Prediction markets like Kalshi give Massie around 72% odds of winning the nomination.

Fundraising favors Massie, who raised $4.95 million through March 31, with $1.47 million cash on hand. Gallrein raised $2.39 million, ending with $1.39 million in cash. The district, spanning northern Kentucky suburbs near Cincinnati and Louisville, is rated Solid Republican by the Cook Political Report.

The contest tests Trump's influence in a deep-red area where Massie's libertarian base has sustained him through past primary challenges. With three weeks remaining, the race remains competitive as both campaigns intensify efforts.