Rep. Thomas Massie, R-Ky., is fighting for his political survival on Tuesday against the combined might of President Donald Trump, his allies, and pro-Israel groups in what has become the most expensive House GOP primary in history.

"I did not see this coming, but my election has become an inflection point for our whole country. Today we make history," Massie posted on X on Tuesday.

Trump has endorsed Ed Gallrein to oust Massie from Congress and the Tuesday primary will see the end of the contest, one way or another. Trump previously backed a primary challenger to Massie in 2020, but later endorsed him in 2022.

The Kentucky Republican's libertarian streak has seen him frequently vote against his own party on budgetary matters, and he has emerged as one of the foremost Republican skeptics of Israel and the ongoing Iran war.

The race itself has become something of a microcosm showcasing divisions within the Republican Party. Whereas Gallrein has portrayed himself as a Trump ally and supporter of Israel, Massie has leaned into his opposition to foreign entanglements and independent streak.

Massie's voting record has also made him something of a darling among libertarian-leaning Republicans and younger voters, with polling showing a stark age split between his supporters and those of Gallrein.

Ben Whedon is the Chief Political Correspondent for Just the News. Follow him on X.