Ed Gallrein, a Republican candidate backed by President Donald Trump, defeated Kentucky Rep. Thomas Massie in GOP primary Tuesday.
The result showed the president's persisting influence over GOP voters, adding to a growing number of Trump-backed primary challengers to defeat Republican lawmakers who angered him in his second term.
Massie, who has served in Congress since 2012, fell into Trump's crosshairs in part by pushing for the release of the Jeffrey Epstein files and denouncing the war in Iran.
Gallrein, a former Navy Seal who avoided making public appearances on the campaign trail, ran on his military service and loyalty to the president. He accused Massie of forsaking Trump and the party.
LIVE RESULTS: Kentucky midterm congressional primaries
Gallrein is expected to win the general election in the deeply red district.
Trump celebrates Gallrein's win over Massie on Truth Social
The president, who had waged his own social media campaign against Massie, posted a photo showing him and Gallrein under the words "Ed Gallrein Wins! Endorsed by President Trump!"
Massie says his race 'started out as an election, turned into a movement'
The Kentucky congressman claimed in his speech after his defeat that young voters were still on his side.
"People that want somebody that will go along to get along, I've never heard of that strategy but that seems to be what the voters want," Massie said. "But not the young voters."
The crowd was still energetic despite Massie's loss, and started a chant of "No more wars!" that the congressman joined in on. Massie's speech meandered through different topics and touched on other politicians before another chant started of "America First!"
"We stirred up something. There is a yearning in this country for someone who will vote for principles over party," Massie said.
Gallrein wraps short speech, vowing to advance president's agenda
After unseating Massie with strong backing from Trump, Gallrein pledged to take the party's agenda to Washington and work closely with the president. His victory speech lasted around five minutes.
"We have a saying on the family farm that it's a contact sport," Gallrein said. "I can tell you that campaigning is one as well folks."
Where Gallrein and Massie got their votes
Gallrein's victory over Massie in Kentucky's 4th Congressional District Republican primary was powered by his performance in Boone, Kenton and Campbell counties in northern Kentucky across the river from Cincinnati, Ohio, and in Oldham County in the Louisville suburbs.
At the time the AP called the race, Gallrein had a lead in all four counties, which collectively make up the bulk of the district vote. Massie was ahead in his home base of Lewis County, but his sizable lead there was still significantly behind the lead he had there in his last contested primary in 2022.