Mamdani-backed progressives win New York primaries, test mayor's influence

Brad Lander defeated Rep. Dan Goldman in New York’s 10th Congressional District, and Claire Valdez won the Democratic primary in the 7th District, handing Mayor Zohran Mamdani two clear wins in the city’s most closely watched House races. Darializa Avila Chevalier was still locked in a tighter contest in the 13th District, where Mamdani had also thrown his support behind her.

The races doubled as an early test of whether Mamdani can translate City Hall momentum into influence beyond municipal politics. He endorsed Lander, Valdez and Avila Chevalier, then stood with them and Sen. Bernie Sanders on June 18 at Kings Theatre in Brooklyn. Mamdani told supporters, “This slate here today is our answer. The Democratic Party must change.” Sanders and the candidates centered the event on working-class issues, immigration and resistance to establishment politics.

Turnout was already a factor before polls closed. New York’s early voting period for the June 23 primary ran through June 21, and unofficial New York State Board of Elections data showed 276,593 ballots were cast over those nine days. Manhattan and Brooklyn led the early vote, underscoring how heavily the contests were concentrated in the city’s most politically active neighborhoods.

The 10th District result carried particular weight because Lander was already a familiar figure there and had led in polling for months. The district includes parts of Lower Manhattan and Brooklyn, including Park Slope, and the race exposed a sharp divide over Israel and Gaza. Lander said Israel was carrying out a “genocide” and opposed military aid, while Goldman backed aid to Israel and criticized Prime Minister Benjamin Netanyahu. That split turned the campaign into a referendum not only on experience, but on the left’s willingness to challenge longstanding Democratic positions.

Valdez’s win in the 7th District was just as symbolically charged. The seat is held by retiring Rep. Nydia Velázquez, who first took office in 1993 and remains a major figure in the city’s Hispanic community. Valdez ran against Antonio Reynoso, Julie Won and Vichal Kumar, with her victory adding another Democratic Socialists of America-aligned candidate to Mamdani’s side of the party’s internal debate. Together, the results gave Mamdani a stronger claim that his coalition can move from protest politics to winning congressional primaries in New York.