Democratic Rep. Dan Goldman has lost his New York City primary to former City Comptroller Brad Lander, NBC News projects, following a battle that highlighted Democratic divisions over Israel and showcased the clout of Mayor Zohran Mamdani, who backed Lander.

Lander won in New York’s 10th Congressional District amid a wave of challenges from Mamdani allies to sitting members of Congress as Mamdani looks to build on his momentum from last year’s election and further reshape the city’s politics.

Goldman had been seen as a rising star in the Democratic Party because of his high-profile role as lead counsel during President Donald Trump’s first impeachment trial. After he narrowly won a crowded primary in 2022, he has been a prominent voice fighting the Trump administration on issues like abortion and immigration. He also leaned on his personal wealth in the primary and touted endorsements from Gov. Kathy Hochul, House Democratic Leader Hakeem Jeffries, D-N.Y., and key labor unions.

But his greatest vulnerability among Democratic voters in a district that pushes down into the rapidly gentrifying corners of Brooklyn was on the issue of Israel. Goldman, who is Jewish, is supported both by the American Israel Public Affairs Committee, a bipartisan group that has drawn the ire of progressives, and the more liberal group J Street, which also designated him an “approved” candidate.

Goldman sought to style himself as a progressive supporter of Israel, seeking to separate criticism of Prime Minister Benjamin Netanyahu and the war against Hamas in Gaza from calls to block military aid to the country.

Lander, who is also Jewish, has been far more critical of Israel’s government and its conduct in the war, which he calls a “genocide.” He has promised to co-sponsor legislation that would put new restrictions on American military aid to Israel and repeatedly sought to use Goldman’s support from AIPAC as a cudgel with Democratic voters who have become more critical of Israel in recent years.

Lander also got a significant boost from Mamdani, whom he made an important alliance with during his own unsuccessful bid for mayor, and won endorsements from national progressives like Sens. Bernie Sanders, I-Vt., and Elizabeth Warren, D-Mass.

He also framed himself as a dogged critic of the Trump administration’s deportation policies, regularly advocating for defendants in federal immigration court, where he was arrested last year after a high-profile altercation with federal officers. A judge found Lander not guilty of misdemeanor charges related to the episode this month.

And he leaned on his work on the City Council and as the city’s chief financial officer to argue that he will be ready to hit the ground running and capture the sense of urgency many Democrats feel in the fight against the Trump administration.