Mamdani-backed candidates score upset wins in New York House primaries

Zohran Mamdani’s three endorsed House candidates swept New York’s Democratic primaries, knocking out two incumbents and putting the mayor’s political reach on display across Brooklyn, Manhattan and Queens. The results became an early test of whether Mamdani is mostly a New York personality or a model other Democrats can copy in primaries where turnout, money and message are all up for grabs.

Claire Valdez won the primary in New York’s 7th Congressional District. In the 10th District, former New York City comptroller Brad Lander defeated Rep. Dan Goldman. In the 13th District, Darializa Avila Chevalier beat Rep. Adriano Espaillat, the chair of the Congressional Hispanic Caucus. Mamdani said the races were about electing “better Democrats” who would put working people back at the heart of politics.

The 13th District fight showed the shape of the coalition behind Mamdani’s project. Avila Chevalier, 32, is a Ph.D. student and pro-Palestinian activist who helped organize protests at Columbia University. She benefited from Mamdani’s endorsement even as AIPAC poured hundreds of thousands of dollars into efforts to blunt her rise. Espaillat entered the race with backing from House Minority Leader Hakeem Jeffries, Gov. Kathy Hochul, New York Attorney General Letitia James and New York City Council Speaker Julie Menin. The Democratic Socialists of America backed both Avila Chevalier and Valdez, underscoring how the party’s left flank helped convert a mayoral endorsement into congressional wins.

The same night, Manhattan’s 12th District delivered another sign of how sharply divided Democratic primaries have become. Micah Lasher defeated Alex Bores and other contenders, including Jake Schlossberg, the grandson of President John F. Kennedy, after AI-industry PACs spent $20 million in the race. Together, the contests showed a New York map pulled by two competing forces: a Mamdani-aligned left that can move votes in city primaries, and well-funded institutional and industry blocs still able to pour millions into the most contested seats. The results also landed alongside primaries and runoffs in Maryland, Utah and South Carolina, giving Mamdani’s allies a bigger stage than city politics alone.