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

Tonight, we'll be monitoring how candidates of color perform in primaries for Senate, House and governor. Overall, 19 people of color — 12 Democrats and seven Republicans — are running in these contests, all for the House.

Each state has a candidate of color running in at least one race, but New York, which also has the most contests overall, is home to 10 of these candidates, including former Rep. Mondaire Jones, who is running in the 17th Congressional District. He tried to switch districts in 2022 due to redistricting and lost the primary in the 10th District, but this year he is running unopposed and hoping to unseat Republican Rep. Mike Lawler.

In Colorado, Democratic incumbent Rep. Joe Neguse is running unopposed in the primary for the state's 2nd Congressional District. In the 3rd District, Stephen Varela, who sits on the state's Board of Education, is the only person of color among six candidates hoping to take on Democrat Adam Frisch for the seat left open by Boebert running in the 4th District this cycle. Asian American Peter Yu, a finance and mortgage consultant, is one of her five challengers in that district. In the 8th Congressional District, are vying to take on the incumbent Democrat, Rep. Yadira Caraveo, a seat Republicans hope to flip in what could be a close race.

Finally, there are currently only four Black Republicans in the House, but Burns could add to that number if he wins his runoff in South Carolina (he is slightly favored against Biggs). Meanwhile, one of those four incumbents, Rep. Burgess Owens, is unopposed in Utah's 4th District.

—Monica Potts, 538