Leading US Democrats are withdrawing their support from Maine Democratic Senate candidate Graham Platner after a former girlfriend accused the politician of sexual assault.

In an exclusive interview with media outlet Politico published on Monday, Jenny Racicot alleged that Platner forced her to have nonconsensual sex in late 2021. She alleged that Platner had entered her Maine home uninvited while intoxicated and forced himself on her, despite her repeatedly telling him to stop.

Platner, whose status as a progressive outsider has gained him popularity, has denied the allegations.

Following Politico’s interview, top US Democrats and Democratic-leaning political groups have pulled their endorsements of Platner.

“I’ve been very clear that sexual assault or violence against women is a red line,” California Democrat Ro Khanna, a member of the US House of Representatives, said. “These allegations are very serious and credible. Graham Platner should drop out from the race. I am withdrawing my endorsement.”

Arizona Senator Ruben Gallego also announced he was pulling his endorsement, while the Maine Democratic Party called on Platner to withdraw his candidacy.

Democratic-leaning political group End Citizens United pulled its endorsement as well, calling the allegations “profoundly disturbing and disqualifying”.

“The conduct described is fundamentally inconsistent with the standards we expect from the candidates we support,” End Citizens United said in its statement.

Hasan Piker, a leftist commentator and streamer who has backed Platner, seemed to reverse his position on Monday following the Politico report. “If new evidence presents itself, I’m going to change my perspective – it’s that simple,” Piker said during a livestream on Twitch.

“This is a clear-cut instance of verifiable sexual assault allegations. It’s completely irredeemable,” he added.

Platner won Maine’s Democratic primary in April, defeating a centrist Democrat from the party’s establishment wing. The race is a must-win for Democrats, facing off against incumbent Republican Susan Collins. Maine state law allows Platner to be replaced on the ballot if he withdraws by July 13. The replacement candidate must be named by July 27.

In a video released on social media, Platner denied the latest allegations but said he was rethinking his campaign.

“Regardless of the inaccuracy of the reporting but mindful of the political reality it will inflict, we’re taking the time to reflect on the best path forward,” he said in the video.

Racicot’s accusations are the latest in the long string of controversies surrounding Platner. A Marine veteran who also worked for a private security contractor, he has a chest tattoo resembling a Nazi symbol – which he denied knowledge of and later had covered up. He has also had a history of controversial statements on social media, as well as reportedly sexting with other women shortly after getting married.