New York City Mayor Zohran Mamdani showed once again his aim to overhaul the politics of the Democratic party on Thursday night by endorsing another candidate seeking to oust a Democratic incumbent.

The mayor’s latest endorsement of democratic socialist Darializa Avila Chevalier over incumbent Rep. Adriano Espaillat, who has represented the 13th Congressional District for nearly a decade, is his third — and he said final — electoral flex after endorsing two other anti-establishment Democrats in closely watched congressional primaries this season.

The mayor’s endorsement of Avila Chevalier comes after his early backing of Claire Valdez, an assemblymember from Queens and fellow democratic socialist, and former City Comptroller Brad Lander in two other high-profile primary races this season that are set to remake the city’s congressional delegation.

Valdez is running against Antonio Reynoso, the Brooklyn Borough president who was endorsed by retiring Rep. Nydia Velázquez, one of Mamdani’s earliest congressional backers ahead of his primary last year. Lander is facing off against Rep. Dan Goldman, who declined to endorse Mamdani at any point before his election but vowed to work with him after his win.

Mamdani made it official Thursday night in a joint appearance with Avila Chevalier on MS NOW’s “The Briefing with Jen Psaki.”

“ This is a New Yorker who has not only secured the release of our neighbors from undue ICE custody, also someone who has been on the front lines of that fight for affordability, and I can't wait for her to be introduced to so many across the city and across this country as we fight for that affordability agenda from New York City to D.C.,” Mamdani said, invoking Avila Chevalier’s working-class childhood and recent fights to help secure the release of detained immigrants, including Palestinian activist Mahmoud Khalil.

Mayor Mamdani endorsed Darializa Avila Chevalier during an appearance on MSNOW.

MSNOW

“As someone who has had to live with the question of whether I can even afford to stay in the city I love, as someone who has struggled with this issue of affordability, but yet seen time and time again my tax dollars, New Yorkers' tax dollars, be used to bomb children and families abroad instead of being invested in our communities here, I am tired of that type of politics,” Avila Chevalier said. “And I'm running because I believe my community deserves the dignity of a representative who is gonna fight tooth and nail for the things that they deserve.”

Espaillat issued a statement late Thursday night citing his endorsements from Democratic leaders including Gov. Kathy Hochul, New York Attorney General Letitia James and House Minority Leader Hakeem Jeffries.

“Mayor Mamdani is entitled to support the candidate of his choice in the race,” Espaillat said. “But one endorsement does not make a race. Voters do.”

Espaillat endorsed Cuomo in the mayoral primary, but in a pledge of Democratic unity was one of the first Cuomo supporters to endorse Mamdani in the general election last year.

The news of Mamdani’s likely endorsement of Avila Chevalier was first reported by The New York Times Thursday afternoon and sent shockwaves across upper Manhattan and the western Bronx district. The Times reported the decision would mark a reversal of an earlier pledge by Mamdani to back Espaillat in this cycle.

Eli Valentin, a political analyst with ties to the 13th Congressional District and author of “Politicking in the Barrio,” said that eight months ago he never thought this would be a competitive race. But the dynamics on the ground have changed.

“Darializa has launched a really strong campaign that has made her credible to the point that I think most observers would say that it may be a 50/50 race at this point,” Valentin said. He said the conventional wisdom had been that Espaillat was a strong incumbent with a very strong base but he said Avila Chevalier’s campaign has fanned out over the district, particularly in parts of Harlem, Inwood and west of Broadway.

Espaillat is no stranger to challenging incumbents. He ran twice against incumbent Rep. Charles Rangel in the district before winning the seat in 2016 in a primary against Rangel’s chosen successor, Keith Wright, a long-serving assemblymember at the time.