Following Zohran Mamdani’s impressive victory in both the primary and general elections in 2025, many believed that his electoral success would not transfer to any other candidates. That he was a one-off politician who only won due to his charisma.
This theory has been proven wrong, as all three of the Mamdani-backed candidates that ran for congress won their elections. Minutes before the polls closed, there was a 22% chance on Kalshi that every candidate would win, but it is all but certain that all three candidates will advance.
Two of the Mamdani endorsed candidates were running against incumbents. These endorsements were incredibly risky and if they failed would have negatively impacted Mamdani’s political power in NYC.
Brad Lander ran against Dan Goldman, the incumbent congressman in NY-12. Rep. Goldman has consistently voted with the Trump administration, and won the 2022 primary with just 25% of the vote. Rep. Goldman also had an unusually high absentee rate in congress, more than three times that of the congressional average.
Lander is the former comptroller, who unsuccessfully ran for the mayoral seat in 2025. He formed an alliance with Mamdani after they cross-endorsed each other on the eve of the primary, and he is credited with much of Mamdani’s electoral success. Lander won by an astonishing 30%, an unprecedented win against an incumbent congressman.
Darialaza Avila Chevalier had the most surprising victory of the night, beating ten year incumbent Rep. Adriano Espaillat. Chevalier had a controversial past, and her resurfaced opinions and tweets from previous years did not help her campaign. She also defended her stance on prison abolition as soon as last week, which caused her odds of winning the election to tank.
However, she pulled off a decent margin of 5% over Rep. Espaillat, winning the election. The strength of the Mamdani endorsement exceeded any political controversies she might have had.
Claire Valdez also won in NY-7, following the retirement of Rep. Nydia Velázques. Rep. Velázques had endorsed her opponent in the race, another example of a Mamdani endorsement overcoming an incumbent advantage. Valdez is a first-termer in the New York state Assembly and ran her campaign by promoting Medicare for all and public housing.
Mamdani has become the next progressive kingmaker, at least in New York. He may be able to replicate his success à la Sanders and become a key figure in progressive races across the country.
What is clear is that Mamdani has extraordinary political might. He was able to beat out two incumbents and one incumbent endorsed candidate, and proved that his victory will provide lasting impact in congress.