After toppling establishment-backed candidates in three New York City primaries, Zohran Mamdani-backed challengers are already on to their next act: upending the lives of congressional Democratic leaders.

The victories of Brad Lander, Claire Valdez, and Darializa Avila Chevalier show the growing power of a progressive bloc that risks stealing the party’s megaphone during a campaign that Democrats had hoped to center on affordability, not aid to Israel. There’s already angst in the party, and glee among Republicans, that the trio will use their new clout to spotlight issues that divide Democrats.

Top House Democrats brushed off the results, with House Minority Leader Hakeem Jeffries urging reporters to “look at the totality of all 215 members of the House Democratic caucus.” But the party’s leaders don’t have to look far to reckon with their increasingly left-wing electorate — both Jeffries and Senate Majority Leader Chuck Schumer live in New York City.

Valdez and Avila Chevalier are democratic socialists, like Mamdani, while Lander is not. That means Republicans are especially keen to make the two far-left women into the faces of the opposition. After redistricting shrank the House battlefield, some Democrats worry that their party is growing more vulnerable to those attacks.

“Nationally, it’s a huge concern,” said purple-district lawmaker Rep. Vicente Gonzalez, D-Texas. He pointed to “how they push the policies within the Democratic caucus that we’re going to have to defend … policies that obviously I don’t agree with, and would be very difficult for me to sell to people in South Texas — and I don’t intend to sell them, because I don’t believe in most of them myself.”

Republicans’ House campaign arm is already trying to tie swing-seat Democrats’ to Valdez and Avila Chevalier, who both have been critical of Israel and have called for abolishing ICE.

The GOP has “got a f*ckton of money, more than us and more than they did in 2018,” one Democratic strategist working on swing-district races told Semafor. “And the far-left primary wins do help the Republicans portray all Democrats as unacceptable.”

Outside the deep-blue bastion of the five boroughs, there was plenty for the mainstream of the Democratic Party to feel good about on Tuesday night. Even in the New York suburbs, a former Palantir employee won the Democratic nod to take on battleground-seat GOP Rep. Mike Lawler.

But intraparty tension pulled focus from that on Wednesday — including the specific strain on Mamdani’s relationship with New York lawmakers. Jeffries, who backed two of the three candidates the mayor helped defeat, didn’t exactly quell that storyline.

“The mayor and I agreed to strongly disagree about some of his endorsements,” Jeffries said. “And he’s got work to do in terms of the conversations that he’s going to have with members of Congress moving forward.”