The left is looking to oust Sen. Kirsten Gillibrand in next year’s Democratic primary — which gives Republicans a chance to take the seat if they can nominate a heavy-hitter for the general.

The Post reported weeks ago on progressives’ ambitions for the seat, and now the left-leaning Daily Beast confirms the “emerging sense among New York insiders” that she’s “vulnerable enough.”

Ironically, she’s so vulnerable to the left for the same reason she’s failed to face a major GOP challenge in the past: She’s had so little impact that most voters barely know who she is.

In a general election in this heavily Democratic state, that gives her enough of an edge that big names shy away. But in a lower-turnout primary, it’s an invitation to well-organized progressives.

On that front, the biggest-name potential challenger is plainly democratic socialist Rep. Alexandria Ocasio-Cortez, whose $5.4 million campaign war chest eclipses the senator’s own $4 million fund. Other possibilities: ex-Rep. Mondaire Jones and Bronx Rep. Ritchie Torres (though he says he’s not interested in running).

Lefties are breathless at the thought of fielding challengers, particularly AOC: “Oh, my God, could she do it,” gushes Ryan Adams, a consultant who often works with progressives. “The apparatus that would spring up around her would be unstoppable. People would fly in from other states to volunteer with her.”  

Progressives feel emboldened despite the message New York voters sent in November’s mini-red wave, when Republicans flipped four House seats and nearly ousted Democratic Gov. Kathy Hochul. Note, for example, the state Senate’s rejection of Hochul’s moderate nominee for chief judge, Hector LaSalle, and lawmakers’ resistance to her push for a tweak in the bail law — even though Republican Rep. Lee Zeldin came closer to winning the gov’s race than any GOPer in years by spotlighting the need for a fix.

All of which means that Empire State voters (but not Democratic primary voters) may be even more primed to reject the left in 2024 than they were in 2022.

Gillibrand, meanwhile, lacks major appeal — as became obvious when she had to drop her 2020 presidential bid only months after launching it. As one Democratic strategist notes, after holding the seat for 14 years, she still lacks any “obvious constituency” who’d rally behind her.

“She is a diminished presence,” quips Hank Sheinkopf, another Dem strategist, flagging her chronic lack of press attention.

From the start, of course, Gilly had to operate in the shadow of New York’s senior senator, now-Majority Leader Chuck Schumer, a relentless headline hunter and national Democratic kingpin. She’s also an obvious chameleon who abandoned her past moderate positions on immigration, guns and spending to please her party’s left wing.

All of which paves the way for an attractive Republican — Zeldin? — to take the seat, especially if a far-left firebrand like AOC wins the primary. At the least, a progressive challenger would pull her further left, away from the majority of New Yorkers furious at how progressive pols are letting crime fester, schools rot and costs rise.

What the Dems do is up to them, but the GOP needs to jump on the first serious chance to retake this seat (previously held by Hillary Clinton) in a quarter-century.