Mayor-elect Zohran Mamdani threw his support behind City Comptroller Brad Lander a day after endorsing his congressional bid, calling him a “trusted ally” who “leads with sincerity.”

Lander on Wednesday announced he would mount a primary challenge to incumbent Rep. Dan Goldman in New York’s 10th Congressional District, saying he had secured endorsements from Mamdani, as well as Public Advocate Jumaane Williams, Sens. Bernie Sanders and Elizabeth Warren and the Working Families Party.

What You Need To Know

Mayor-elect Zohran Mamdani threw his support behind City Comptroller Brad Lander a day after endorsing his congressional bid, calling him a “trusted ally” who “leads with sincerity”

Lander on Wednesday announced he would mount a primary challenge to incumbent Rep. Dan Goldman in New York’s 10th Congressional District

Lander, a onetime City Council member, is the only primary challenger thus far to Goldman in the race for NY-10, which comprises lower Manhattan and parts of Brooklyn

In a statement, Mamdani called Lander a “trusted ally and partner.”

Fielding questions at day care center in Chelsea Thursday morning, the mayor-elect said he was “proud to endorse Brad.”

Thrilled to welcome the endorsement of my friend (and NYC Mayor-elect) @ZohranKMamdani as we continue to fight for the city that we love. pic.twitter.com/R7d1f4x5io

— Brad Lander (@bradlander) December 11, 2025

“Brad is a friend, he’s an ally, he’s a partner. And I’ve appreciated the relationship that we’ve had over the time that we’ve been elected officials,” he said. “And also the one that we built as we were running in this campaign for much of the last year.”

As mayoral primary candidates, Mamdani and Lander cross-endorsed each other in an effort to block former Gov. Andrew Cuomo’s bid to run the city.

Following the June 24 primary — in which Lander placed third — the city comptroller began campaigning for Mamdani.

“I think Zohran’s gonna win big. There’s just so much energy,” he said in an October interview with NY1. “So many people out knocking doors. No one’s out knocking doors for Andrew Cuomo.”

Lander, a onetime City Council member, is the only primary challenger thus far to Goldman in the race for NY-10, which comprises lower Manhattan and parts of Brooklyn, including Lander’s longtime neighborhood, Park Slope.

Progressive City Councilmember Alexa Avilés and former state Assemblywoman Yuh-Line Niou — both of whom were mulling their own challenges to Goldman — released separate statements Wednesday saying they would not enter the race.

Lander referenced his relationship with Mamdani in his campaign launch video.

“Our mayor [could] have an ally in Washington instead of an adversary in his own backyard,” he said, referring to Goldman.

While Goldman met with Mamdani after the June primary, he did not endorse him, noting that there were “issues that we agree on as well as other critical ones where we do not.” The two diverge in their stances on Israel, among other issues.

Goldman has not yet publicly commented on Lander’s entry into the race.

Mamdani, for his part, described Lander as “someone who leads with sincerity, with knowledge, with fluency and with empathy.”

“And I think New Yorkers would stand to benefit if his leadership continued in our city,” he said. “And that’s why I was so excited to endorse him and I will continue to work to support him so that he can continue to be a leader in this city.”