Five-term incumbent Rep. Adriano Espaillat was defeated in the Democratic primary Tuesday night in what political observers are calling a stunning upset by newcomer Darializa Avila Chevalier — a political earthquake not just for New York City politics, but also for the Congressional Hispanic Caucus, which Espaillat chairs.

Avila Chevalier was backed by New York City Mayor Zohran Mamdani, a fellow democratic socialist who was a kingmaker on Tuesday night, with all three of his progressive picks winning their races. Two of those Mamdani endorsed, including Avila Chevalier, defeated incumbent Democrats.

But Espaillat, a power broker in Washington and in the Upper Manhattan and Bronx-based district, was the biggest sitting lawmaker targeted by New York progressives, in what some liberal leaders are calling a progressive Tea Party, similar to the conservative movement that toppled incumbent Republicans in 2010.

Espaillat was the first Dominican American elected to Congress and the first formerly undocumented immigrant to serve as a congressional lawmaker. Avila Chevalier is also of Dominican descent and is Muslim.  

House Democratic leaders downplayed the losses of incumbents to Mamdani-backed candidates in deep-blue New York City districts. They said Wednesday they are focused on battleground districts that will deliver them the 218 seats they need to secure the majority in November. 

"Our focus, our agenda is 218, and nothing that the mayor did helps or hurts us getting to that number," said Rep. Pete Aguilar of California, the chairman of the Democratic Caucus and a member of the Congressional Hispanic Caucus. 

Rep. Suzan DelBene of Washington, the chair of the Democratic Congressional Campaign Committee, added, "Our focus is on the districts that get us the majority." 

Aguilar argued the wins of democratic socialist candidates are a "recoil" against the president and his policies, rather than a reflection on the Democratic incumbents. 

The Congressional Hispanic Caucus has more than 40 members from both parties, including progressive Reps. Alexandria Ocasio-Cortez of New York and Greg Casar of Texas. Ocasio-Cortez — whose district spans a part of Queens known as the "Commie Corridor" and the Bronx — declined to weigh in on Avila Chevalier's race, though Ocasio-Cortez is a fellow democratic socialist and also rose to prominence by defeating a powerful sitting Democrat in a 2018 primary.

In Espaillat's remarks to supporters on Tuesday night, he harkened to his personal history as an immigrant.

"When I came to this nation as a young, immigrant boy, I never could have imagined I would be a member of Congress," he said. "That is the privilege of my life." 

An activist and Columbia doctoral student, Avila Chevalier attempted to run to Espaillat's left on issues like immigration, housing and Israel. Supporters of Espaillat, himself a progressive, sought to cast some of her views as radical.

Chuck Rocha, a Democratic strategist and an expert on Latino outreach, said the "irony is, Espaillat is an immigrant."

"He's an advocate for immigrant rights," Rocha said. " It's a shame when we're spending money to beat good Democrats when we could be spending it to beat Republicans." 

Espaillat had received financial backing from several super PACs, including Latino Victory Fund, which supports Latino Democrats, and Bold America, which was founded by Congressional Hispanic Caucus members. But he also had the financial backing of a super PAC affiliated with American Israel Public Affairs Committee, which supports pro-Israel politicians. 

Avila Chevalier, like other democratic socialists, seized on the contributions from an AIPAC-linked group, including at a debate earlier this month.

"He is somebody who has taken $670,000 from AIPAC, all while voting to send our tax dollars to a country that is enacting a genocide," Avila Chevalier said at the June 16 debate.

In response, Espaillat said he supported a two-state solution to the Israeli-Palestinian conflict and condemned Avila Chevalier's participation in a pro-Palestinian rally the day after Hamas' Oct. 7, 2023 attack on Israel. "She doesn't believe in the existence of Israel," Espaillat said. 

In 2024, she also an helped organize pro-Palestinian protests at Columbia University, which is in the district, and she counts  Mahmoud Khalil, the pro-Palestinian activist detained by ICE last year, as a friend. 

Espaillat, 71, was first elected in 2016, after twice unsuccessfully challenging powerful Rep. Charlie Rangel, a 20-term power broker in the Harlem-area district. But the district's boundaries have changed to include more of the Hispanic areas of East Harlem, Washington Heights and the Bronx, and the area has become more gentrified and diverse. Over 50% of the district's population is made of Latinos, according to 2024 research by Data USA.

During the campaign, an aide to Espaillat, who is now on leave, accused Avila Chevalier of working with Mamdani to replace the Dominican community with Haitians and Muslims, City & State reported. According to The New York Times, Espaillat on Tuesday did not respond to questions about his supporters falsely claiming Avila Chevalier is Haitian, but instead reminded voters of his own heritage. He later called for all to "lower the temperature of this campaign." 

"I am the first Dominican American to be elected to the House of Representatives," Espaillat said. "I think I bring a different perspective to the table that's never been heard before."