Three progressive candidates backed by New York City Mayor Zohran Mamdani swept primary elections on June 23, 2026, in a major show of force for the left-wing faction of the Democratic Party in New York’s primary elections. Brad Lander, Darializa Avila Chevalier, and Claire Valdez all won their Democratic nominations for House seats, with two of them unseating sitting members of Congress.
Lander, the former New York City comptroller, defeated two-term incumbent Representative Dan Goldman in New York’s 10th Congressional District. Chevalier, a state legislator, ousted five-term incumbent Representative Adriano Espaillat in the 13th District. Valdez, a state assemblywoman, won the open seat in New York’s 7th Congressional District, which was being vacated by retiring Representative Nydia Velázquez.
Mamdani, who was elected as the city’s mayor in November 2025, is a member of the Democratic Socialists of America and has leveraged his political capital to support a slate of candidates aligned with the democratic socialist movement. The three victories signal the growing influence of the left wing within New York’s Democratic Party and represent a significant challenge to the party’s establishment wing in one of the nation’s most important urban centers.
The race in New York’s 10th District, which Lander won, was marked by sharp divisions within the Democratic Party over the Israel-Gaza war, according to reporting on the primary elections. Goldman, a wealthy lawyer who had served two terms in Congress, faced criticism from progressives over his positions on Middle East policy. Lander’s victory over an incumbent in a competitive primary underscored the degree to which Mamdani’s endorsement carries weight among Democratic voters in New York City.
In the 13th District, Chevalier’s victory over Espaillat, who had represented the district for five terms, demonstrated similar momentum for the progressive slate. Both Lander and Chevalier are aligned with Mamdani’s democratic socialist politics, and their wins suggest that voters in these districts are receptive to candidates running to the left of the Democratic establishment.
Valdez, who describes herself as a democratic socialist, won the open-seat race in the 7th District with support from Mamdani and Vermont Senator Bernie Sanders. She defeated Brooklyn Borough President Antonio Reynoso and other candidates in a crowded primary field. The three victories collectively represent a significant expansion of democratic socialist influence in New York’s congressional delegation and a validation of Mamdani’s strategy of backing aligned candidates in high-profile races.
Sources
- The New York Times — Reported that Mamdani-backed candidates swept House primaries on June 23, 2026, with Lander defeating Goldman and Chevalier beating Espaillat.
- AP News — Confirmed that top allies of Mayor Zohran Mamdani defeated establishment-backed Democrats in New York’s congressional primary elections, ousting two incumbents.
- CNBC — Reported that three progressive candidates endorsed by Mamdani won Democratic primaries for House seats, ousting two incumbents.
- BBC — Noted that Lander unseated Goldman in a race that laid bare the city’s divisions over the Israel-Gaza war.
- Politico — Reported that Valdez, with a boost from Mamdani, defeated Brooklyn Borough President Antonio Reynoso in the open NY-7 primary.
- Democratic Socialists of America — Confirmed that Mamdani, a democratic socialist and DSA member, was elected NYC mayor in November 2025.
- NPR — Reported that all three progressive candidates backed by Mamdani won their primary races, including two who took on Democratic incumbents.
