Republican senators are starting to wobble on confirming Pete Hegseth as President-elect Trump urges the Defense Secretary nominee to "keep fighting" against a media smear campaign.

Opposition to Hegseth's nomination was instantaneous, as critics blasted his unconventional background as a Fox News host and seized on an allegation that he sexually assaulted a married woman in 2017. Hegseth said the encounter was consensual, and police at the time declined to pursue charges.

Backlash has continued to mount, as liberal news organizations publish a series of anonymous accounts attacking Hegseth's character.

Republicans wobble on Hegseth

Hegseth can afford to lose only three Republican votes and still be confirmed. But some Republican senators are starting to cast doubt on his confirmation, including Lindsey Graham (R-Sc.), who called anonymous claims against Hegseth "very disturbing."

"I think some of these articles are very disturbing. He obviously has a chance to defend himself here, but some of this stuff is -- it's going to be difficult. Time will tell,” Graham said.

The leftist rag New Yorker published an anonymous story claiming Hegseth was fired by veterans' groups over drunk behavior. Hegseth has attributed the claims to jealous ex-colleagues.

A board member from one of those groups wrote a 2016 letter to Fox News that surfaced Wednesday, defending Hegseth, saying he left voluntarily.

In the letter, which surfaced Wednesday, Randy Lair of Concerned Veterans for America said Hegseth left "as a result of a difference of opinion as to the future of the organization and so that he could focus on other endeavors, including his relationship with Fox News."

Brett Kavanaugh 2.0

The smear campaign against Hegseth has gone to a deeply personal level. The New York Times published a leaked email from Hegseth's mother criticizing his treatment of women during his second divorce.

The media onslaught has been likened to the treatment that Supreme Court Justice Brett Kavanaugh received during his confirmation hearing, which was rocked by a series of increasingly outlandish, uncorroborated claims of sexual misconduct that delved into his high school life.

“I had a member, not 45 minutes ago, look me in the eye in private, just he and I, and say, ‘That’s what they’re trying to do to you … that’s their playbook, get ready for more, and they’re going to make it up, just like they have so far," Hegseth told The Megyn Kelly Show.

"All anonymous, all innuendo, all rumor, nothing sourced, no verification, and they’re just gonna keep doing it because you’re a threat to them.'”

Hegseth not backing down

Hegseth's mother appeared on Fox and Friends Wednesday to address her leaked email, which she said she instantly regretted sending. Penelope Hegseth apologized in a follow-up email that was not published.

“I want people to look at Pete and understand him for who he is today,” she said. “And to disregard the media — that was seven years ago — and most of that was misinformation.”

Hegseth, an Army veteran, has said he is not backing down and that President-elect Trump is behind him.

"He said keep going, keep fighting. I'm behind you all the way," Hegseth said Wednesday.

"Why would I back down? I've always been a fighter. I'm here for the war fighters. This is personal and passionate for me."