Government watchdogs on Monday called for Rep. Duncan Hunter's immediate resignation after it was reported that the California Republican would change his "not guilty" plea to "guilty" in the case of his alleged campaign finance violations.

Hunter told KUSI Newsin San Diego in an exclusive interview which aired Monday that he plans to plead guilty on Tuesday to using $250,000 in campaign funds for personal expenses and falsifying Federal Election Commission (FEC) records to conceal the purchases.

The six-term congressman said he planned to plead guilty to avoid a public trial.

The watchdog group Citizens for Responsibility and Ethics in Washington (CREW) said on social media, "We're glad he'll finally face consequences for his actions," and called on Hunter to resign.

Duncan Hunter has shown a blatant disregard for the law & engaged in one of the most egregious spending scandals we've ever seen. We're glad he'll finally face consequences for his actions. Now that he'll be convicted for criminally abusing his office, he must resign immediately. — Citizens for Ethics (@CREWcrew) December 2, 2019

.@CREWcrew filed multiple complaints years ago against Congressman Duncan Hunter for using many thousands in campaign funds for his personal benefit. He was charged criminally and tomorrow will plead guilty. Now he must resign.https://t.co/NxMwDELPG7 — Noah Bookbinder (@NoahBookbinder) December 2, 2019

Hunter was accused of misusing the funds over a year ago. Like President Donald Trump, who Hunter endorsed early in the 2016 presidential election, the congressman spent months deriding the charges against him as a "witch hunt." He won re-election three months after the allegations came to light.

Hunter's expected guilty plea will make him the second loyal Trump supporter to admit to committing a felony in two months. In October, former Rep. Chris Collins (R-N.Y.) pleaded guilty to insider trading soon after announcing his resignation.

Collins and Hunter were the first and second members of Congress to endorse Trump, and the president vehemently defended both against their charges.

Tomorrow, Duncan Hunter will become the second Trump-supporting congressman to run an extensive campaign claiming they were the target of a witch hunt and then subsequently admit to doing crimes. https://t.co/f1bZv1opbR — Ryan J. Reilly (@ryanjreilly) December 2, 2019

Robert Maguire, research director for CREW, noted that Hunter and Collins are just two Trump allies and associates now facing criminal charges.

So for those playing along at home: - After tomorrow, the first two members of Congress to endorse Trump in 2016 will be convicted felons - Trump's campaign manager and longtime personal lawyer are both in jail - Trump's deputy campaign manager will be sentenced soon — Robert Maguire (@RobertMaguire_) December 2, 2019

Among Hunter's alleged misuses of his campaign funds were purchases made in connection with several affairs he had with lobbyists and congressional aides—violating the congressional code of conduct. His expected guilty plea comes weeks after the resignation of former Democratic Rep. Katie Hill, a fellow Californian who stepped down in October, days after admitting to a romantic relationship with a campaign aide. Misuse of campaign funds was not included in the accusations against Hill, who was also the victim of having sexually explicit images of her released without consent.

Several political observers pointed out the sharp contrast between Hunter's decision to continue serving in Congress and run for re-election with the full support of the president, and Hill's immediate resignation.

Duncan Hunter used campaign funds to finance his fancy lifestyle and pay for affairs with at least five women-- three lobbyists and two Congressional staffers--and will serve out the remainder of his term while Katie Hill quit after being the victim of revenge porn by RW media. — Joshua Holland (@JoshuaHol) December 2, 2019

I'm old enough to remember when Rep. Katie Hill was forced to resign for far less. https://t.co/N13K7BwDrm — Julia Ioffe (@juliaioffe) December 2, 2019

Hunter indicated Monday that he will leave Congress before the 2020 election, telling KUSI that he "wants his seat to remain in Republican hands and he will try to ensure a smooth transition."