Political reporter Leigh Ann Caldwell issued a dire warning for President Donald Trump on Tuesday, predicting that if Rep. Thomas Massie (R-KY) manages to come out victorious in Tuesday night’s GOP primary race, the president may suffer among his most significant defeats seen yet.Trump has poured enormous political capital into ousting Massie after he infamously bucked the president in leading the charge to force the release of files related to Jeffrey Epstein. The president recruited retired Navy SEAL Ed Gallrein to run against Massie, with voters set to make their decision Tuesday night.Should Massie lose to Trump’s hand-picked challenger, it would “just reinforce” Trump’s strength in deciding GOP primary races, Caldwell said during an appearance Tuesday on CNN. But if Massie wins, Caldwell suggested, it could be a turning point for Trump’s sway among Republicans.“If Thomas Massie is defeated, it will show Donald Trump's grip on the party, and it'll also show that money is a huge, huge factor still, even in these primary races in rural Kentucky,” Caldwell said. “But the bigger shock will be if Thomas Massie wins. That will be a huge, huge defeat for the president and a sign of big defiance and might from this lone congressman from Kentucky.”The race between Massie and Gallrein has gone on to become the single-most expensive House primary race in U.S. history, with at least $25.6 million being spent across both candidates, though a larger share has been spent in support of Gallrein. A considerable amount of spending against Massie has come from pro-Israel groups, with Massie being among the few members of Congress to openly criticize Israel for its ongoing siege on Gaza, which has been labeled a genocide by countless human rights groups.