Brad Lander, endorsed by New York City Mayor Zohran Mamdani, won the Democratic primary in New York's 12th congressional district on Tuesday, defeating two-term incumbent Dan Goldman by a dominant margin. The victory, announced just minutes after polls closed at 9 p.m., underscored the growing influence of Mamdani's progressive coalition and signaled a shift in the party's stance on Israel's war in Gaza.
Landslide Victory and Progressive Wave
With 92% of votes counted, Lander led Goldman by 31 points, according to unofficial results. Cheers erupted at Lander's victory party in Brooklyn at 9:04 p.m. as the former city comptroller and mayoral candidate was declared the winner. The win was part of a broader sweep for Mamdani-backed candidates, with Claire Valdez and Darializa Avila Chevalier also winning their primaries. All three are expected to win the general election in November, adding a new progressive bloc to Congress.
“What a glorious time to be a New Yorker,” Lander told the crowd. “These past few weeks there has been a powerful energy moving through our city, a generosity of spirit, a refusal to give up even against very long odds, and a feeling of joy out in the streets, shared by every kind of New Yorker there is.” He added, “Give it up for the New York Knicks, all right.”
Mamdani's Influence and Cross-Endorsement
Lander and Mamdani, who competed against each other in the 2025 mayoral election, later formed a cross-endorsement to leverage ranked-choice voting for a progressive win. Mamdani introduced Lander at the party, calling him a “good friend” and praising his “kindness” and “sincerity.” Mamdani's win last year was fueled by youth support, and the crowd at Lander's party reflected that energy, with many young attendees citing Mamdani as their introduction to Lander.
“Mamdani and Brad Lander obviously competed in the mayoral election originally, and I think after Brad endorsed Mamdani, that's what brought Brad to my attention,” said Ian Ryan, 24. “I think Brad's policies are progressive and forward thinking, and he cares about the people in his district.”
Gaza Stance a Key Issue
The primary was heavily shaped by the candidates' positions on Israel's war on Gaza. Lander, who is Jewish, has been an outspoken critic of Israel, calling its actions in Gaza genocide. Goldman, also Jewish, took a less critical stance and was endorsed by the pro-Israel American Israel Public Affairs Committee (AIPAC), which spent millions opposing progressive Democrats. Lander referenced the party divide in his victory speech, vowing to be “one of the Jewish members of Congress most willing to stand up for Palestinian human rights” and acknowledging that “Democrats are painfully divided by our differences about the US relationship to Israel and Palestine.”
For voters like Kate Dalton, 42, who volunteered for Lander's campaign, the Gaza issue was decisive. “I know him as someone who shows up, and also because he's taken a moral stand on Gaza, and that was really important to me,” she said.
A Fighter for Immigrant Rights
Lander has a history of activism on immigrant rights, including two arrests during his mayoral campaign protesting detentions under Donald Trump. In September 2025, he was arrested during a protest, and this month he was found not guilty of blocking an elevator while inspecting rooms holding detained immigrants. “We need fighters, and he is a fighter,” said supporter Léa Zimmerman, 34. “He is a presence, he actually follows through, and he's consistent.”
Victory Party Atmosphere
The party, held near Brooklyn's Barclays Center, featured free drinks, fried chicken, cajun fries, and popcorn with nutritional yeast and aonori. Tables offered tote bags for $40 and free posters, including one depicting a bicycle, basketball, hotdog, and pigeon. Supporters wore political pins, with Zimmerman sporting a badge reading “No ICE please.”
Lander's win marks a significant moment for New York's progressive movement, with Mamdani-backed candidates poised to reshape the city's congressional delegation.
