A Long Island activist and former Democrat who recently switched political parties to challenge US Rep. Andrew Garbarino in the Republican primary is feeling heat over her progressive past.

Cait Corrigan, 24, who is vying to become the youngest member ever elected to Congress, promotes herself on her campaign website and social media as a Donald Trump-loving, staunch conservative who opposes vax mandates and “illegals” entering the country – as part of the “next generation fighting for America first.”

But Corrigan’s GOP bonafides are relatively recent. Sources said she became a registered Republican mere months ago, while her Democratic roots date back to her adolescence.

In 2008, a then 10-year-old Corrigan was the youngest New York volunteer working for Hillary Clinton’s presidential campaign, according to a Newsday report at the time which cited local Democrats.

Ten years later, in an essay about her experience as a summer intern for the World Organisation Against Torture in Switzerland, Corrigan slammed the United States, questioning “how we can create peace” in the US considering it was “built on theft, genocide, slavery, and institutionalized misogyny.”

“The United States of America, with our unanimous support and involvement within imperialism and global capitalism has notoriously led to the continual oppression, discrimination, and murder of marginalized groups of people and their culture from Tibet, Afghanistan, to Syria, Mexico, and Rwanda, Yugoslavia, to Palestine, Venezuela, Yemen, and Myanmar,” added Corrigan, whose college essay was posted, along with dozens of others, by the Long Island Area Council of Unitarian Universalist Congregations.

Corrigan, of Patchogue, NY, is an ordained Christian minister, her website says.

The 2^nd Congressional District – whose predominately white upper middle-class population includes southwest Suffolk County and part of southeastern Nassau County – is now considered a Republican stronghold that supported Trump in the past two presidential elections.

Garbarino, 37, was elected to Congress in November 2020 after 14-term GOP incumbent Peter T. King decided to not run. He previously served eight years as a state Assemblyman and worked as a lawyer.

Anthony Pileggi, a political consultant for Garbarino’s re-election campaign, questioned whether Corrigan switched parties because being a Republican nominee is the clearest path to victory.

On Friday, she posted a picture of herself with Trump at Mar-a-Lago to Instagram, with the message, “45 & 47! My President. Let’s MAGA Again!”

“Cait Corrigan is a former registered Democrat activist who has a history of troubling anti-American rhetoric,” Pileggi said.

“She is now trying to run as an American First Republican, and I think Long Island voters will see right through her candidacy. Contrast that with Rep. Garbarino’s long record of delivering results for Long Island and voters will have an easy choice this year.”

Corrigan, however, shot back Saturday, saying in a statement she’s a “home-schooled constitutionalist, a Trump supporter and a patriot” while “Andrew GarbaRINO is a weak-spine party insider who’s providing the communists in Congress the means to take over our country.”

“His campaign reeks of desperation, basing attacks off a photo from when I was a 10-year-old girl and an intern application written to appease a leftist professor,” she insisted.

“RINO” is an acronym for politically dissing someone as a “Republican In Name Only.”