Republican Congressman Thomas Massie of Kentucky faces his toughest electoral test yet as Trump-endorsed challenger Ed Gallrein, a farmer and retired Navy SEAL, contests his seat in Tuesday's GOP primary — one of the most expensive House primaries in U.S. history, with over $25 million in ad spending. Massie, a 14-term MIT-trained engineer known for his libertarian-leaning conservatism, drew Trump's ire after voting against the president's flagship budget legislation over deficit concerns, opposing the war in Iran, and pushing for the release of the Epstein files. Polls show an unusually tight race for a congressman who has previously won by comfortable margins, highlighting a broader tension within the Republican Party between loyalty to Trump and independent-minded conservatism.