Mamdani-backed candidate challenges moderate incumbent Dan Goldman in closely watched Democratic primary
The Challenge to Democratic Establishment Power
City Comptroller Brad Lander announced Wednesday that he will challenge incumbent Representative Dan Goldman for Congress, setting up a decisive Democratic primary in New York’s 10th District that will test progressive momentum following Zohran Mamdani’s mayoral victory. The race marks a significant moment in which Mayor-elect Mamdani openly backs a challenger to an establishment Democrat, signaling willingness to reshape New York’s congressional delegation. Lander released a campaign video emphasizing his roots in the district and record of fighting corruption and protecting renters.
The Political Stakes and District Dynamics
The 10th Congressional District presents unusually fertile ground for progressive challenge. Covering Lower Manhattan and western Brooklynincluding Park Slope where Lander previously served on City Councilthe district overwhelmingly supported Mamdani in both the 2025 mayoral primary and general election. Goldman, a Levi Strauss heir and former federal prosecutor first elected in 2022, narrowly survived that crowded primary by consolidating support among more moderate voters while progressives split their votes.
Lander’s campaign video directly challenges Goldman’s positions, particularly regarding AIPAC and foreign policy. Without naming Goldman directly, Lander criticized lawmakers doing “AIPAC’s bidding” and allowing the wealthy to buy Congressional seatsexplicit references to Goldman’s pro-Israel positions and self-funding that totaled nearly $5 million in his previous campaign.
The Relationship Between Lander and Mamdani
Lander and Mamdani cross-endorsed each other during the June mayoral primary, with Lander positioning himself as the responsible adult in a field that included Mamdani. Many observers expected Lander to join the incoming administration as deputy mayor or other senior official. However, tensions emerged during the summer, with sources suggesting Mamdani grew frustrated by what he perceived as Lander’s self-aggrandizing positioning. After Mamdani’s general election victory, he declined to offer Lander a top position, instead encouraging him to challenge Goldman.
This unexpected reversal has transformed what appeared to be a close political partnership. Mamdani has now publicly endorsed Lander’s Congressional bid, demonstrating both his political reach beyond city limits and willingness to challenge incumbents perceived as insufficiently progressive on Palestine and economic justice.
Policy Differences and Israel-Palestine Context
The race encompasses fundamental disagreements about Middle East policy and what progressive politics means. Goldman, a strong Trump critic and lead counsel for House Democrats during Trump’s first impeachment, has consistently supported Israel and criticized Mamdani’s rhetoric around Palestine. Before the mayoral general election, Goldman stated he remained “very concerned about some of the rhetoric coming from Zohran Mamdani” regarding anti-Israel activism, particularly around the phrase “globalize the intifada.”
Lander, a self-identified liberal Zionist, has moved progressively leftward on Israel-Palestine questions, influenced partly by conversations with his daughter who studied Holocaust history and Raphael Lemkin’s concept of genocide. Lander has described Israeli military actions as ethnic cleansing and called for conditioning military aid to Israel, positions that align more closely with Mamdani’s Palestine solidarity activism.
Building a Winning Coalition
Lander enters the race with significant advantages. Data for Progress polling conducted in September showed Lander defeating Goldman 52-33 in a hypothetical matchup. He has secured endorsements from Senators Bernie Sanders and Elizabeth Warren, the Working Families Party, and Public Advocate Jumaane Williams. National progressive figures view the race as a test case for replacing establishment Democrats with more ideologically consistent progressives.
However, challenges remain. City Council Member Alexa Avilés, closely aligned with the Democratic Socialists of America and reporting interest in the seat, could fragment the progressive vote if she enters. Some Democratic strategists note that Avilés might have higher ceiling as a congressional candidate, particularly given her appeal to the district’s 20 percent Latino population and likely DSA endorsement.
Lander’s Record and Message
As comptroller, Lander highlighted anti-corruption efforts, affordable housing advocacy, and tenant protection as defining achievements. His office claims responsibility for preventing 50,000 families from losing homes to eviction. More recently, he participated in civil disobedience against Immigration and Customs Enforcement operations, getting arrested twice at federal buildings while supporting detained immigrants. His willingness to break laws for immigrant rights has elevated his standing among progressives and directly contrasted his activism with Goldman’s more procedural approach.
The Broader Reshaping of New York Politics
Goldman’s race represents one of several competitive New York Democratic primaries shaping the party’s future direction. In Manhattan’s 12th District, nine candidates are running to replace retiring Representative Jerrold Nadler. In the Bronx, Assemblywoman Amanda Septimo, aligned with Mamdani, is challenging Representative Ritchie Torres. These races collectively indicate whether the progressive left can consolidate power beyond city elections into the Congressional delegation.
For Lander, the race offers redemption after falling short in the mayoral primary. For Mamdani, the endorsement demonstrates his political machinery extends beyond New York City government into shaping regional representation. The outcome will signal whether 2025 represents an inflection point in New York politics toward sustained progressive organizing power or a temporary peak vulnerable to pushback from Democratic establishment forces.
