Mamdani-backed progressives score primary wins amid Gaza, Israel divide

Zohran Mamdani-backed candidates won three competitive New York City Democratic congressional primaries on June 23, ousting two sitting House members and taking an open seat in a sweep that jolted the city’s party establishment. Brad Lander defeated Rep. Dan Goldman in the 10th Congressional District, Darializa Avila Chevalier beat Rep. Adriano Espaillat in the 13th, and Claire Valdez won the 7th District race to replace retiring Rep. Nydia Velázquez.

The results gave Mamdani, the New York democratic socialist who rose to prominence in 2025, a broader bench of allies just weeks after he appeared with Lander, Valdez and Avila Chevalier at a June 18 get-out-the-vote rally. Their victories were built on campaigns that openly challenged U.S. support for Israel’s war in Gaza and questioned the influence of pro-Israel political money, making the primaries a direct test of whether pro-Palestinian politics had moved from the margins into a more durable Democratic faction.

In the 10th District, the clash between Lander and Goldman became the clearest proxy fight over Israel. The race centered heavily on their differences over the war and over how aggressively Democrats should confront the Biden-era approach to Israel and Gaza, with Lander leaning into the issue as Mamdani’s public ally. The same divide shaped the other contests, where Valdez and Avila Chevalier ran as part of a broader progressive lane that has tried to turn outrage over Gaza into an electoral force inside the city party.

The Associated Press described the outcome as a resounding show of force for Mamdani and his effort to reshape the Democratic Party, and the scale of the wins gave that argument real weight inside New York’s coalition politics. But the question for Democrats beyond the city is whether the lesson is transferable or confined to a handful of districts where progressive turnout, activist networks and candidate messaging aligned. Establishment Democrats have warned that sharply anti-Israel positions could still alienate swing voters in places where the party cannot afford defections.

For now, the June 23 primaries showed that Mamdani’s rise did not end with his own breakthrough. In Lower Manhattan, Brooklyn, Queens and the Bronx, his allied candidates turned the Gaza debate into a winning message, and at least for one election night, they made room for it inside the Democratic mainstream.