If Biggs wins her race in South Carolina’s 3rd, that will be notable not only because the Trump endorsee would lose, but because the GOP has been slow to nominate women for safe Republican seats. Earlier in the cycle, in North Carolina’s 13th (a safe red seat), Kelly Daughtry was a contender, where she was set to face off against Brad Knott in a runoff. However, Trump endorsed Knott ahead of the runoff, and she dropped out.

—Meredith Conroy, 538 contributor

The AP reports that about 82 percent of the expected vote has reported from the GOP primary runoff in South Carolina's 3rd District, and Biggs's lead over Burns now stands at around 4 points, 52 percent to 48 percent. Looking at the results from the South Carolina Election Commission, Burns has not gotten the boost from the Election Day vote that we expected. In fact, Biggs leads among votes cast on election day, 53 percent to 47 percent, and that group of votes looks set to make up close to 80 percent of the final overall vote total. (Biggs leads 51 percent to 49 percent among the smaller number of early and absentee votes.)

—Geoffrey Skelley, 538

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

In Tuesday's marquee race, Democratic Rep. Jamaal Bowman could lose renomination against Westchester County Executive George Latimer in New York's dark blue 16th District. This race is defined by internal Democratic divisions over the Israel-Gaza conflict, the influence of pro-Israel groups and controversies about Bowman's past behavior. Bowman has joined with fellow members of the progressive "Squad" and some other Democrats to criticize and oppose U.S. support for Israel, a position that made him a major target for pro-Israel groups.

Bowman lacks a strong electoral record, having won only 54 percent of the primary vote in his first reelection campaign in 2022. He also attracted scrutiny last September when he pulled a fire alarm in a Capitol Hill office building just before a high-profile vote to avoid a government shutdown, for which he was censured by the House and had to pay a fine. On top of this, old blog posts by Bowman came to light in January that included conspiracy theories about the terrorist attacks on Sept. 11, 2001. All of this has helped boost the primary challenge from Latimer, who's also built up a strong local political reputation in Westchester County — where 9 in 10 of the district's voters live, according to Daily Kos Elections.

Still, the big story is Latimer's support from pro-Israel donors and organizations. Latimer has raised $5.8 million, $2.4 million of which came via individual donors who used the American Israel Public Affairs Committee as a conduit to contribute to his campaign. This has helped give him a financial leg up on Bowman, who has raised $4.3 million. And the monetary disparity grows far starker when we look at outside spending. Groups have spent a whopping $17.7 million either opposing Bowman or supporting Latimer, according to OpenSecrets, while they've spent only $3.0 million attacking Latimer or boosting Bowman. As a result, this has turned into the most expensive House primary on record, according to AdImpact.

The principal group behind the massive spending is United Democracy Project, a super PAC affiliated with AIPAC, which has forked out $14.6 million on the race to take down Bowman. Despite the pro-Israel connection, the group's ads rarely mention the ongoing conflict, instead criticizing Bowman on issues such as not supporting President Joe Biden's position on a major infrastructure package in 2021 and a debt ceiling deal in 2023. Bowman and his allies haven't taken this lying down. In the last primary debate, Bowman attacked the "racist MAGA Republicans" — a reference to AIPAC's bipartisan sources of financial backing — supporting Latimer, a criticism leveled in ads put out by Bowman and outside groups backing him.

The most recent survey of the race — an Emerson College/The Hill/WPIX poll from early June — found Latimer ahead of Bowman 48 percent to 31 percent, which signals just how in danger Bowman is of becoming the first Democratic incumbent to lose renomination in 2024.

—Geoffrey Skelley, 538