WASHINGTON, DC - JANUARY 10: Rep. Duncan Hunter (R-CA) speaks to the media before a painting he found offensive and removed is rehung on the U.S. Capitol walls on January 10, 2017 in Washington, DC.

Rep. Duncan Hunter, R-Ca, is expected to appear in federal court on Tuesday to plead guilty for spending more than $200,000 in campaign funds on personal expenses, according to the San Diego Union-Tribune.

The representative and his wife were charged with 60 criminal counts of campaign finance violations in August 2018. The couple allegedly misused campaign funds, spending it on vacations, gas, groceries and surgeries, among other personal expenses.

According to Politico, Hunter told TV station KUSI in San Diego that "Tomorrow, on Tuesday, I'm going to change my plea to guilty."

He also indicated that he will not run for re-election.

Hunter has denied any wrongdoing for years. He initially pleaded not guilty, referring to his own prosecution as a "witch hunt" when he and his wife were charged.

"There has been a constant barrage of misinformation and salacious headlines in our media regarding this matter," he said in a statement last year. "I purposely choose to remain silent, not to feed into this witch-hunt and trust the process."

Margaret Hunter, his wife and former campaign treasurer, took a plea deal earlier this year, admitting to her role in the scandal and agreeing to testify against her husband. That put pressure on the congressman to strike his own deal.

Federal Election Commission finance rules prohibit using campaign funds for personal use.

Hunter's trial was scheduled for Jan. 22. The California lawmaker, who's about to turn 43 this Saturday, did not immediately reply to a request for comment from CNBC.