The political shockwaves of Assemb. Zohran Mamdani's dramatic New York City Democratic mayoral primary victory reverberated across Long Island Wednesday as some local officials expressed wariness of Mamdani, with some labeling him as anti-American and antisemitic. 

Mamdani, a 33-year-old democratic socialist from Astoria, emerged victorious Tuesday in a primary that included former New York Gov. Andrew M. Cuomo. Mamdani's progressive agenda gravitated voters who rejected the more mainstream and well-known Democrat in Cuomo.

But in Nassau and Suffolk counties, where the Republican base has only grown in the Trump era, Mamdani's message has hit much differently among elected officials.

Nassau County Executive Bruce Blakeman, a Republican and strong ally of President Donald Trump, described Mamdani in an interview as “an antisemite” and “anti-American.” And Rep. Laura Gillen, a fellow Democrat, criticized Mamdani for “a deeply disturbing pattern of unacceptable antisemitic comments which stoke hate at a time when antisemitism is skyrocketing.”

Rep. Tom Suozzi (D-Glen Cove) was more measured in his comments about Mamdani compared to Gillen. Suozzi endorsed Cuomo in the primary and said in a post on X that he remained concerned about Mamdani’s mayoral candidacy.

Gillen, however, said in a statement that Mamdani was “too extreme to lead New York City” and his campaign was built on “unachievable promises and higher taxes.”

“He is the absolute wrong choice for New York,” said Gillen, of Rockville Centre.

Mamdani did not respond to a request for comment regarding the elected officials' remarks. 

Mamdani, a practicing Muslim, has said that criticism of Israel and advocacy for Palestinian rights — and how the country's conducted the war in Gaza — are not akin to antisemitism. He's said he believes in equality for all in Israel.

New York’s top two congressional Democrats — Senate Minority Leader Chuck Schumer and House Minority Leader Hakeem Jeffries — did not endorse any candidates during the primary, but both said on Wednesday they had spoken with Mamdani and planned to meet with him in person soon.

On the other side of the aisle, Rep. Andrew Garbarino (R-Bayport) in a statement to Newsday called Mamdani's agenda "out of touch" and "dangerous."

"Government-owned grocery stores didn’t work in Russia, and they sure as hell won’t work in New York City," Garbarino said, referring to Mamdani's proposal to establish city-operated grocery stores — one per  borough — to address food deserts in low-income neighborhoods and keep prices low.

Rep. Nick LaLota (R-Amityville) did not respond to a request for comment.

Mamdani, while earning the Democratic nod for November's general election, must still contend with incumbent Mayor Eric Adams, who is running as an independent, in the general election. Cuomo also did not rule out an independent run.

While Mamdani is now considered the favorite to win, given the overwhelming number of registered Democrats, recent political history has shown that a November victory is not a guarantee. In Buffalo, democratic socialist India Walton won her 2021 primary against mainline Democrat and incumbent Byron Brown only to lose to Brown in the November general. This came after Brown waged a successful write-in campaign.

Schumer, in a social media post, said Mamdani “ran an impressive campaign that connected with New Yorkers about affordability, fairness, & opportunity.” And he said he’s known Mamdani “since we worked together to provide debt relief for thousands of beleaguered taxi drivers [and] fought to stop a fracked gas plant in Astoria.”

Jeffries (D-Brooklyn) appeared on MSNBC’s “Morning Joe” on Wednesday and said Mamdani’s “relentless focus on affordability had great appeal all across the city of New York.”

Hank Sheinkopf, a political consultant who has worked for Cuomo in the past, said the ripple effects of Mamdani on Long Island may be to strengthen the Republican strongholds and drive moderate and conservative city residents to the suburbs if he becomes mayor.

“People in Suffolk County hear the word socialist, they will lose their minds,” he said, adding that an “emerging population” of Central American voters on Long Island also shun socialist branding.

Sheinkopf said he doesn’t believe the way Mamdani connected with younger voters carries over to a similar demographic growing up on Long Island. He said the younger people involved in labor, members of fire departments and who are starting small businesses will look at Mamdani and say, “He’s not our plate of soup.”

Shoshana Hershkowitz, founder of the activist group Suffolk Progressives, said in an interview that Mamdani's message of affordability and quality of life applies everywhere, whether urban, suburban or rural. She said she doesn't believe many of the Mamdani voters would consider themselves socialists, but rather "liked the platform."

"I think that too often we get to this very like tribal red, blue, and it really is about what can government do for people to make their lives better," she said, adding that Mamdani's primary win gives her hope for Long Island.

Suffolk County Executive Edward P. Romaine, a Republican, said in an interview Wednesday that Mamdani’s win didn’t come as a shock since he had seen predictions in recent weeks that he could win. He said he believes the win will have implications for all communities surrounding New York City.

“Because there’s concern about public policy and how it will affect the city’s interaction with their surrounding counties,” he said at an unrelated news conference Wednesday.

Blakeman recounted Mamdani’s comment in a 2024 interview about ordering Israeli Prime Minister Benjamin Netanyahu's arrest if he were to visit New York City under Mamdani's tenure. It’s antisemitic to single out Israel from “other countries that really have human rights issues” like Venezuela, China, Russia, Cuba or North Korea, Blakeman said.

"New York City is the financial capital of the world, it's predicated on capitalism, and to have a mayor that's a socialist — to me — is completely counterintuitive,” Blakeman said. “I'm very troubled by how radical the Democratic Party has become in New York City."

Newsday’s Matthew Chayes contributed to this story.