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

The Republican primary in Colorado's 8th District — one of the most competitive House districts in the nation — is causing a bit of intraparty drama (a common theme tonight). Republicans here are hoping to unseat first-term Democratic incumbent Rep. Yadira Caraveo in this highly competitive district that spans the Denver suburbs and rural counties to the north. (Caraveo is the first person to hold the seat, which was created after apportionment in the 2022 cycle.) At first blush, Gabe Evans would seem like a shoo-in for this race. He's an Army vet, former police officer and former state representative who has outraised his competitor, and he's been endorsed by both Trump and the Koch brothers' Americans for Prosperity. But his competitor, retired doctor and former state Rep. Janak Joshi, got the controversial state party endorsement. As a result, it's unclear which direction the voters in this district may ultimately go, and if the candidate they choose will be strong enough to defeat Caraveo.

—Kaleigh Rogers, 538

In the Republican runoff in South Carolina's 3rd District, 12 percent of the expected vote has reported, and Biggs leads Burns by about 8 percentage points, 54 percent to 46 percent, according to the Associated Press. Remember, Burns has Trump's endorsement, but the early returns suggest a potentially close race. Still, there's a long way to go.

—Geoffrey Skelley, 538

In Colorado's 5th District, around Colorado Springs, there's a competitive GOP race to replace retiring GOP Rep. Doug Lamborn. The battle is between conservative radio host Jeff Crank and Dave Williams, the state GOP chair. Along with his talk radio gig, Crank has a background in politics, having previously worked as a regional vice president for Americans for Prosperity, and a staffer for former Rep. Joel Hefley.

Crank is the more traditional conservative pick, whereas Williams, a former state representative, has made a name for himself in the state as a MAGA provocateur and has been endorsed by the political arm of the far-right House Freedom Caucus. In 2022, when he challenged Lamborn in the primary, Williams petitioned (and failed) to add the slogan "Let's Go Brandon" to his name on the ballot, and as leader of the state party, he has taken it on a polarizing and notably hard-right tack. Under his leadership, the party advised county canvass boards not to certify the 2022 election results, and has sent out emails calling LGBTQ+ pride month "evil." It has also started endorsing candidates in primaries, something the party historically remained neutral on.

Perhaps unsurprisingly, this has led conservative power brokers to dump millions into the race: The Koch Brothers' PAC has spent over $100,000 supporting Crank, while a super PAC of Republican megadonors has spent $1.2 million opposing Williams. As the only district in the state to have never been represented by a Democrat in Congress, the GOP primary will be a crucial one to watch to see if the ranks of the Freedom Caucus are likely to grow by one.

—Kaleigh Rogers, 538