Truth-challenged Long Island Rep. George Santos will announce his reelection campaign Monday in Washington D.C., a source told The Post.

Despite facing multiple calls to resign from both parties over a series of lies about his personal and professional life, the Republican congressman has “called big donors and sat down with supporters and believes he can raise $500,000 to $750,000 in the second quarter of 2023,” said a person close to Santos.

“Many of us Americans are willing to accept all sorts of resurrection, perhaps Representative George Santos will be another,” said entrepreneur Josh Eisen, a top Santos donor — who declined to say whether he would back him again.

Santos is currently facing a House ethics probe stemming in part from his fibs about his background.

There is also a federal investigation into his campaign’s finances.

Some of Santos’ most vocal critics have come from inside his district’s own local Republican party.

Nassau County GOP boss Joseph Cairo said Santos had “disgraced the House of Representatives” and waged a campaign of “deceits, lies and fabrications” in order to win the vote of New York’s Third Congressional District.

The party is all but certain to run a vigorous primary challenge against him. Long Island State Sen. Jack Martins is said to be a favorite of Cairo’s.

Nassau County legislator Mazi Melesa Pilip and Stefano Forte, a former GOP State Senate candidate, have also been floated.

There have been whispers about Queens GOP City Councilwoman Vickie Paladino or Councilwoman Inna Vernikov getting into the race.

Cairo previously told The Post he’d been contacted by ten potential aspirants.

“If the field is crowded enough and Santos keeps running to the right, it’s possible he could skate by with a plurality,” said Gavin Wax, president of the New York Young Republicans, who backed Santos’ 2022 campaign. “He needs to build a cult following and continue to humanize himself.”

If Santos survives a primary, he would face a well-financed Democrat in a general election campaign.

The party has declared its seat a top priority in 2024 and has already allocated millions of dollars for the effort.