During his tumultuous time in Congress, former Republican lawmaker George Santos became known for his flamboyant narcissism. But at a criminal court on Long Island Monday, Santos tried something new: penitence.

The 36-year-old serial fraudster was remorseful as he admitted to a litany of financial crimes, for which he faces at least six years in prison.

"This plea is not just an admission of guilt," Santos said Monday. "It's an acknowledgment that I need to be held accountable like any other American that breaks the law."

Santos pleads guilty

It's a stunning turn of fortune for the notorious con man who hustled his way to Congress with a fabricated life story that unraveled weeks after he won office.

As Santos fell under scrutiny, he was charged with ripping off donors and cheating taxpayers out of unemployment benefits.

A House investigation found Santos used campaign money to pay for designer clothes and Botox, among other personal expenses. Santos lasted less than a year in Washington before he was expelled in a historic vote backed by fellow Republicans.

Santos pled guilty to wire fraud and aggravated identity theft Monday at a courthouse in Central Islip, New York.

The Republican was remorseful and verging on tears, admitting he is "flooded with deep regret."

"It is clear to me now that I allowed ambition to cloud my judgment, leading me to make decisions that were unethical," Santos said. "Pleading guilty is a step I never imagined I would take, but it is a necessary one, because it is the right thing to do."

"I failed you"

Santos had previously pled not guilty before reversing course, averting a September trial.

In addition to his prison sentence, Santos owes $370,000 in restitution. His defense lawyers said he doesn't have the money to pay it back.

"We will see how it goes, but I see substantial problems if he can't comply," Federal Judge Joanna Seybert said.

His sentencing is on February 7, with a sentence ranging from 75 to 87 months.

Santos apologized to his former constituents in the 3rd district, which covers parts of Nassau County and neighboring Queens.

"It has been the proudest achievement of my life to represent you, and I believe I did so to the best of my abilities, but you also trusted me to represent you with honor and to uphold the values that are essential to our democracy, and in that regard, I failed you," Santos said.