Nathaniel, I think it's hard to undersell $17.7 million in outside spending in New York's 16th District race on behalf of Latimer or against Bowman. AdImpact says this was the most expensive primary ever, and about 4 in 5 dollars spent on ads in the race were from Latimer's side. Much of that was from the AIPAC-affiliated super PAC United Democracy Project, so the easy answer is to say Israel.

However, I don't want to overlook Bowman's various weaknesses and Latimer's strengths, which also were major contributors. Bowman wasn't strong to start with — he won only 54 percent of the primary vote in 2022 — and he'd suffered from more recent controversies such as pulling a fire alarm in a House office building and 9/11 conspiracy theory postings found on his old blog. Tellingly, groups like UDP mostly attacked Bowman for his past votes that didn't align with Biden rather than go after him on Israel. Latimer, meanwhile, has a long history in Westchester politics and may be about the strongest possible challenger Bowman could've gotten in this primary.

—Geoffrey Skelley, 538

Nathaniel, I won't shy away from what I see as the big weaknesses for Bowman: Democratic progressives right now are upset at incumbents for the high cost of living and America's pro-Israel policies, so it's likely he lost some votes there — as evidenced by a projected decline in turnout from his constituency (from 90,000 votes in 2020 to around 70,000 today, if I reverse-engineer the AP's "expected vote" math).

But the bigger, um #ackshually answer I'll offer is that he was never that popular in the district. In 2020, when Bowman won his primary victory against unpopular incumbent moderate Democrat Eliot Engel, he won by only 14 points. And in 2022, he faced no real primary threat, inflating his appearance of a dominant incumbent.

The money spent for George Latimer by outside groups, of course, also likely has a lot to do with tonight's results. PACs don't spend over $20 million in U.S. House primary elections for nothing!

—G. Elliott Morris, 538

OK, guys, there are going to be a lot of hot takes out there tonight and tomorrow about why Bowman lost. But this is a smart, data-driven crew. What do you all think was the primary reason?

—Nathaniel Rakich, 538

The AP projects that New York Rep. Claudia Tenney will win the Republican primary in New York's 24th District. We figured she was favored, but Tenney only defeated the same opponent, businessman Mario Fratto, by 14 points in the 2022 primary here, so we were keeping an eye on this one. However, with 36 percent of the expected vote reporting, Tenney leads 65 percent to 35 percent, per AP, so she looks set to survive and win reelection in this solidly red Upstate seat.

—Geoffrey Skelley, 538

Amid the many primaries taking place tonight, voters in Colorado's 4th District are also choosing their next member of Congress. Buck, frustrated with his own party, resigned from the House early, triggering a special election to fill out the remainder of his term.

Though Boebert is running for a full term in this district, she isn't running in the special. Instead, Republicans nominated Greg Lopez, the former mayor of Parker, Colorado, and a 2022 candidate for governor. Lopez faces Democrat Trisha Calvarese, a speechwriter, in what should be an uncompetitive special election tonight.

But there's at least an outside possibility the race could surprise us. Democrats recently overperformed in another House special election, in Ohio's 6th District, that was thought to be a walkover for the GOP. That seat, vacated by Republican Bill Johnson, had voted for Trump by 29 percentage points in 2020, but the GOP nominee won by 9 points, an overperformance of 20 percent. Colorado's 4th District voted for Trump by 19 points in 2020, so a similar overperformance would result in a very tight race.

However, there are plenty of reasons why that may not be the case. Unlike in Ohio, where the special election was the only race happening in the state and turnout was in the basement, the Colorado special election is concurrent with a statewide primary race that will boost turnout. And in the 4th District specifically, a contentious primary featuring Boebert and a bunch of other candidates will probably boost Republican turnout specifically.

But it wouldn't take a Calvarese win to be good news for Democrats. Historically, special election results have some predictive power, and Democrats have been putting together a healthy record so far ahead of the 2024 elections. Since the beginning of 2023, Democrats have overperformed partisanship in House special elections by 7 points, according to a 538 analysis, and in special elections overall by a similar margin.

At a moment when national polling looks middling at best for Democrats, a stronger-than-expected showing tonight could provide some much-needed comfort.

—Jacob Rubashkin, Inside Elections