UNIONDALE, N.Y. – The shift of two major New York City suburbs to the political right could be a boon for former President Trump on Election Day, according to insiders on both sides of the aisle.

Traditionally purple, if not leaning blue, Long Island’s Nassau and Suffolk counties went solidly red in the 2022 midterms even though state voter rolls show Democrats outnumber Republicans in both places.

And that may be a bellwether of where things are headed in similar communities around the country.

Former President Trump narrowly won Suffolk County in 2020, beating Joe Biden by fewer than 250 votes. But then, in the 2022 midterms, both Suffolk and the neighboring Nassau County, which borders the Big Apple, saw red waves in local and congressional elections.

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Supporters of former President Trump, the Republican presidential nominee, wait for the start of his campaign rally at Nassau Veterans Memorial Coliseum Sept. 18, 2024, in Uniondale, N.Y. (Michael M. Santiago/Getty Images)

"I think the real catalyst was the crazy way that the Democrats were managing both Washington and Albany," Nassau County Executive Bruce Blakeman, a Republican, told Fox News Digital. "Now, when you talk about cashless bail, when you look at our insecure borders . . . we're spending billions of dollars on people who have been here for 15 minutes rather than hospitals, infrastructure, schools. People are fed up."

Trump's message resonates more with suburban voters, he said.

"I think the Democrats are the ones that are helping us the most, and I think moderate Democrats and independent voters want to vote Republican now because they're fed up with the policies of Biden-Harris," he said.

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Nassau County Executive Bruce Blakeman speaks ahead of former President Trump at a rally in Uniondale, N.Y., Wednesday, Sept. 18, 2024. (Julia Bonavita/Fox News Digital)

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Laura Curran, a pro-police Democrat who opposed the state's controversial bail reform law, said despite her positions, rhetoric from far-left lawmakers on Capitol Hill hurt her campaign when she lost her re-election bid to Blakeman three years ago.

"Talking about who is the standard-bearer of your party is really, really important," she said. "That’s why its good Biden is gone, and Kamala Harris is in."

Still, she said, the state's unpopular governor, Kathy Hochul, is another weak spot after a new Siena College poll found that her favorability among New York voters has fallen below Trump's.

Gov. Kathy Hochul speaks during an announcement on the inclusion of money for the Mental Health and Public Safety Budget for fiscal year 2025 at the Midtown Community Justice Center.  (Lev Radin/Pacific Press/LightRocket via Getty Images)

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At Trump's rally Wednesday, the former president said former U.S. Rep. Lee Zeldin, who is from Suffolk County and tried to unseat Hochul in the last gubernatorial race, could have a role in his next administration if he wins re-election. The capacity crowd erupted in cheers.

Hochul squeaked by with a win over Zeldin by less than 5% in a state where registered Democratic voters outnumber registered Republicans by more than two to one.

Crime in general and especially migrant crime are at the forefront of voters' minds, as are taxes and the economy, polls show.

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In Suffolk, the former president's Justice Department played a major role in combating a plague of MS-13 violence, something the police union there hasn't forgotten.

"That was a gang that had a death grip on Long Island," said Lou Civello, the Suffolk Police Benevolent Association (PBA) president. "They were targeting young individuals to either join the gang or die. That's what we were dealing with."

Members of the Suffolk County Police Benevolent Association attend a tailgate ahead of former President Trump’s rally in Uniondale, N.Y., Wednesday, Sept. 18, 2024. (Julia Bonavita/Fox News Digital)

And the gang carried out numerous brutal murders with machetes as their weapon of choice. In one case, gang members killed a mother and then slaughtered her young child to prevent him from growing up and seeking revenge, Civello said. Then, one of the killers took one of the murdered child's toys and brought it home for his girlfriend's son to play with.

"It was a problem that needed more than just local policing," Civello said. "We needed a federal partner, and President Trump made it a priority."

The Suffolk PBA became the first police organization in New York to endorse Trump's re-election bid earlier this year. 

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Supporters of former President Trump are ready and waiting outside the Nassau Coliseum for Trump's rally in Long Island Sept. 18, 2024. (Fatih Aktas/Anadolu via Getty Images)

After Trump left office, the Biden-Harris administration gave itself a black eye by reversing Trump's remain in Mexico policy, opening a floodgate that some Republican leaders passed on to sanctuary states and cities, bussing and flying migrants from the border to places like New York, Martha's Vineyard and Chicago.

That led to what New York City police called "a wave of migrant crime" earlier this year as the newly imported Venezuelan prison gang Tren de Aragua quickly grabbed headlines for spearheading a spike in robberies.

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Attendees enter former President Trump’s rally in Uniondale, N.Y., Wednesday, Sept. 18, 2024. (Julia Bonavita/Fox News Digital)

"Every town is a border town now," Civello told Fox News Digital.

Trump's message at the rally Wednesday clearly resonated with voters. He pledged to crack down on migrant crime and slammed progressive cashless bail policies, moves he said would make New Yorkers "love" their home state again.

Levittown, Hicksville and Uniondale are some of the country's original suburbs, he noted.

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"These were great, great towns where you grew up, and you loved, and you stayed," he said, to cheers.

Still, while he vowed to be the first Republican presidential candidate to win New York in decades, he faces an uphill battle.

People wait outside Nassau Coliseum before the start of a rally for former President Trump, the Republican presidential nominee, Wednesday, Sept. 18, 2024, in Uniondale, N.Y. (Ted Shaffrey/AP)

Recent Siena College polling shows New York's suburban counties slightly favor Trump over Harris, 50% to 48%, and Trump is ahead in the Upstate region 50% to 45%. But Harris is ahead in New York City 72% to 25%.

A new Fox News Poll shows Trump's suburban advantage in the Empire State is greater than the national average, which favors Harris and Minnesota Gov. Tim Walz 51% to 47% for Trump and Ohio Sen. JD Vance.

If Trump's gains on Long Island are a bellwether for similar communities in the key swing states, it could be huge for his re-election bid.

"I think Long Island is a very good barometer for suburbia in America," said Melissa DeRosa, a top adviser to former Gov. Andrew Cuomo.

Vice President Kamala Harris, the Democratic presidential nominee, speaks at the Congressional Hispanic Caucus Institute Leadership Conference at the Ronald Reagan Building in Washington on Wednesday, Sept. 18, 2024. (AP Photo/Jose Luis Magana)

"Suburbs, in general, traditionally are purple," she explained. "They can swing in either direction, and I think women in the suburbs in particular have a lot of voting power in the electorate. When I look at Long Island, and you see this encroachment in the last couple of years, where it's gone completely red, even under a good scenario for us in terms of the lines being drawn, I think it's a real wake-up call."

Trump continues to deliver messages in different communities specifically tailored to their needs, she said, pitching "no tax on tips" in Nevada and tariffs on foreign cars to the United Auto Workers union.

"People respond to leadership," she said. "They respond to a lack of leadership. And I think that the problem is that, in 2020, it was enough to not be Trump. In 2024, it's not enough to not be Trump when, resoundingly, poll after poll after poll, people feel worse off economically  . . . when the direction of the country is as negative as it is, when inflation is where it is, when geopolitically, things are such a mess."

Still, she said, she doesn't expect Trump to win the deep blue state.

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But in the key swing state Pennsylvania, suburbs outside Philadelphia are also showing signs voters are headed to the right, according to David Gelman, a Trump campaign legal surrogate whose family owns restaurants there.

"I can tell you, you are seeing Trump flags all over, and it's not even close," he told Fox News Digital. "They're putting a ton of effort into Pennsylvania, because if you win Pennsylvania, there's a good possibility that you're winning the presidency."