Billionaire investor Bill Ackman vowed on Wednesday to provide “hundreds of millions of dollars” to back any viable challenger against Democratic socialist Zohran Mamdani in New York City’s mayoral race.
Mamdani defeated former Governor Andrew Cuomo in New York City’s Democratic primary on Tuesday and will compete against incumbent Mayor Eric Adams (running as an independent this cycle) and Republican nominee Curtis Sliwa in the November general election.
Ackman, founder and chief executive of hedge fund manager Pershing Square Capital, wrote a lengthy post on X to express his alarm at Mamdani’s victory.
“I awoke this morning gravely concerned about New York City,” Ackman wrote. “I thought ‘What has NYC become that an avowed socialist who has supported defunding the police, whose solution to lowering food prices is city-owned supermarkets, who doesn’t understand that freezing rents will only make apartments scarcer and more expensive in the long run.'”
The billionaire investor compared a potential Mamdani-led New York to “another failed major city run by Democrats alongside Seattle, Chicago, LA, and SF,” quoting Senator John Fetterman’s (D-PA) assessment that Mamdani’s victory represented “Christmas in July for the GOP.”
“A mayor who disrespects the NYPD and has called for their defunding will get less effective policing, and Bratton’s ‘broken window theory’ will operate in reverse,” Ackman wrote, warning that New York City would become “much more dangerous and economically unviable” under Mamdani’s administration.
Ackman assured potential candidates that funding would be instantly available, stating, “there are hundreds of million of dollars of capital available to back a competitor to Mamdani that can be put together overnight,” and adding that he is “in the text strings and the WhatsApp groups” organizing the effort.
The financier noted that any challenger would likely need to run as a write-in candidate, but suggested this could become “an important call to action that brings people in throngs to the polls” rather than a disadvantage.
I awoke this morning gravely concerned about New York City. I thought “What has NYC become that an avowed socialist who has supported defunding the police, whose solution to lowering food prices is city-owned supermarkets, who doesn’t understand that freezing rents will only…
— Bill Ackman (@BillAckman) June 26, 2025
New York City, with a gross metropolitan product of $2.3 trillion and a population exceeding 8 million residents, is America’s financial nerve center. Many on Wall Street reacted with dread following Mamdani’s primary win, and predicted a mass exodus from the city if he is elected in November.
Mamdani, a state assemblyman representing parts of Queens, has championed policies that alarm fiscal conservatives and moderate Democrats alike. His platform includes advocating for city-owned supermarkets, rent freezing measures, and significant reallocations of police funding to social services.
Ackman expressed particular concern about Mamdani’s stance on Israel, noting that “a mayor who condones hate speech will incentivize more hate speech and violence,” adding that “words matter, and yes, they can inspire people to kill as we have recently tragically seen in our country and around the world.”
Mamdani has stated that he doesn’t believe Israel has a right to exist as a Jewish state, refused to condemn calls to “globalize the intifada,” and recorded a rap song expressing “love” to convicted Hamas financiers. His October 7 statement notably focused on “ending the occupation” with little mention of Hamas’ massacre of Israeli civilians.
Ackman suggested that former Mayor Michael Bloomberg might play a significant role in any challenge to Mamdani, stating that he was “sure that Mike Bloomberg will share his how-to-win-the-mayoralty IP and deliver his entire election apparatus and system to the aspiring candidate.”
The investor called on his followers to “crowdsource” potential candidate names and conduct polling to identify the most viable challenger.