Part of Zohran Mamdani's campaign centers around the belief that billionaires shouldn't exist. Now, those ultra-wealthy earners are aiming to stop the mayoral candidate, in part, by boosting the profile of former New York Governor Andrew Cuomo, Mamdani's opponent for this cycle.

Part of Mamdani's bid has been to tax the ultra-rich and wealthy corporations, which include an additional 2% tax on New Yorkers earning more than $1 million a year. Despite these multi-million dollar oppositions, Mamdani is maintaining a lead in the mayoral race.

Some of the groups opposing Mamdani include "Fix the City" (pro-Cuomo committee) and "Defend NYC" (a group made to oppose Mamdani). Fix the City has raised $7.3 million since the primary, Defend NYC has raised almost $2.5 million, according to Business Insider.

Now, roughly 26 billionaires and rich families from around the U.S. have spent at least six figures to support Cuomo, according to an analysis from Forbes. They estimate the total amount equates to over $22 million to back opposition campaigns, including from billionaires Bill Ackman and former New York City Mayor Michael Bloomberg.

Fortune has reached out to Mamdani's team for comment.