Utah 2nd District Rep. Celeste Maloy is the last moderate incumbent in Utah who has drawn a right-wing challenger, and she may be in slightly more danger than the others. Not only did she lose the state party's endorsement at its April convention, but she only narrowly won the Republican nomination for this seat in a 2023 special election with 39 percent of the vote. Her opponent this time around, Army veteran Colby Jenkins, has also raised a credible $379,000, and tea party-aligned outside groups have spent $534,000 to support him. But while Jenkins has the influential support of Lee, Trump's last-minute endorsement of Maloy may have halted Jenkins's momentum.

—Nathaniel Rakich, 538

We're also keeping an eye tonight on a few mild-mannered Republican incumbents who are probably safe for reelection but have displeased the GOP's right flank enough to earn a primary challenge.

For example, hardline state Rep. Phil Lyman won the state GOP's official endorsement for governor over incumbent Gov. Spencer Cox at an April party convention, but a HarrisX/Deseret News/University of Utah poll earlier this month showed Cox leading Lyman 71 percent to 29 percent among the broader primary electorate. (Republican conventions in Utah, which are largely attended by dogmatic party activists, tend to be more conservative in their tastes than voters.)

Similarly, in the 1st District, electrician Paul Miller defeated Rep. Blake Moore at the party convention and could tap into some level of discontent with Moore's moderate voting record, but he's raised all of $4,706 for the cycle, so he's unlikely to actually defeat the incumbent.

—Nathaniel Rakich, 538

The Republican primary to replace Curtis in Utah's 3rd District is far more unsettled than the Senate race. In the absence of any polls, fundraising numbers make this look like a two-person race between trampoline baron Case Lawrence and Roosevelt Mayor Rod Bird. Lawrence, who founded the indoor trampoline park chain Sky Zone, has brought in $2.8 million ($2.5 million of which was self-funded) and has styled himself as an optimistic problem-solver opposed to hardline tactics like government shutdowns. By contrast, Bird, who loaned himself $1.0 million of the $1.2 million he's raised, has used more partisan language and has pledged to "tie the hands of Congress" unless it balances the budget.

Three other candidates, though, could still be factors despite being underfunded. State Sen. Mike Kennedy has the backing of conservative Sen. Mike Lee and, while he's raised only $587,000, he has raised more from individual donors than any other candidate. Romney, meanwhile, is supporting his nephew-in-law, former Utah County GOP Chair Stewart Peay. And state Auditor John Dougall is running as the race's only explicit anti-Trump candidate.

—Nathaniel Rakich, 538

Kaleigh, tonight could be a bad night for Trump endorsees. One (Staggs) is already the underdog to win, and a second (Burns) is now in real danger of losing in South Carolina. And some of his other endorsees, like Williams, aren't shoo-ins either …

—Nathaniel Rakich, 538