Graham Platner, Democratic candidate for U.S. Senate, speaks at an event hosted by Sen. Bernie Sanders in Orono on May 24. (Robert F. Bukaty/Associated Press)

Graham Platner is facing a flood of calls to withdraw from the Maine Senate race in the wake of a sexual assault allegation a Maine woman made in a story published by Politico.

The Maine Democratic Party on Monday called for Platner to withdraw, and national party leadership and funders followed suit, saying Platner could no longer unseat Sen. Susan Collins in light of the allegations.

High-profile supporters such as Sen. Elizabeth Warren of Massachusetts and Rep. Ro Khanna of California also pulled their endorsements after Jenny Racicot, a Maine Democrat, told Politico that Platner forced her to have sex with him in 2021. They had been dating about two years when she said he arrived at her home drunk and forced himself on her.

Platner denied the allegations. But the Maine Democratic Party called on him to drop out, citing previous reports about his alleged mistreatment of women.

“Maine Democratic Party leadership takes seriously our responsibility to hold every candidate who seeks to represent our state to the highest standard,” the party’s leadership said in a written statement.

“Over the past several weeks, multiple women have made serious, credible allegations against Graham Platner. Today’s statements take those allegations even further,” they continued. “Maine Democratic Party leadership is calling on Graham Platner to withdraw as the Democratic nominee for U.S. Senate.”

The statement was signed by Chairman Charlie Dingman, Vice Chairman Imke Schessler and Executive Director Devon Murphy-Anderson.

“The Maine Democratic Party leadership stands with women and survivors, and that principle does not bend based on party affiliation,” the statement continued. “We respect the women who made the hard decision to come forward. Speaking up is often costly.”

Platner’s campaign did not immediately respond to a question about the party’s statement.

Platner also lost the backing of one of his most steadfast supporters, former Maine Senate President Troy Jackson.

“There is no place in our politics for sexual violence. Not in our party, not in any party. Graham Platner must withdraw from this race today,” Jackson said in a statement released by a spokesperson.

It has been a stunning reversal for Platner, the 41-year-old oyster farmer and combat veteran who was nominated last month to take on Republican Sen. Susan Collins in what’s expected to be one of the most closely watched Senate races in the country. He cruised to the nomination after Gov. Janet Mills suspended her campaign in April.

Democrats need to flip four seats to control the Senate, and Maine’s seat is considered the best of their best pickup opportunities. Collins is the only Senate Republican running in a state won by Democrats in the 2024 presidential election. And Republicans are facing headwinds such as President Donald Trump’s low approval ratings.

Platner said in a video statement Monday after the Politico story was published that he’s weighing “the best path forward.”

The rapid erosion of his support appears to leave him with few options.

Senate Democratic Leader Chuck Schumer and DSCC Chair Senator Kirsten Gillibrand said in a statement that Democrats couldn’t defeat Collins if Platner remains on the ballot.

“Graham Platner needs to immediately withdraw as the Democratic nominee for Senate and allow Maine Democrats the opportunity to choose a new candidate,” the senators from New York said.

Key Democratic funders have also pulled their support.

“Senate Majority PAC is redirecting resources away from the Maine Senate race in light of the latest allegations against Graham Platner,” Lauren French, the PAC’s spokesperson, said in a statement. “We continue to believe this seat is winnable if Platner is not on the ballot, but we cannot strategically continue to invest here when there is an expansive battleground map where these resources can help win a Democratic majority.”

Warren, a progressive stalwart, told Semafor she had seen enough.

Sen. Elizabeth Warren holds a rally for Graham Platner April 18 at the Holiday Inn by the Bay in Portland. (Daryn Slover/Staff Photographer)<?xml version="1.0"?> Purchase this image

“Now more than ever we need leaders in Washington who reflect our values. There can be no tolerance for sexual assault,” Warren said according to a post on the digital news site. “Working families are counting on Democrats to win the Senate election in Maine to unrig our economy and hold Donald Trump accountable. With so much at stake, the best path forward is for Graham Platner to step aside as the Democratic nominee and address these serious allegations outside this Senate race.”

Khanna, D-Calif., campaigned with Platner and defended him after national reports surfaced about his alleged mistreatment of women. But on Monday, Khanna withdrew his endorsement and called on Platner to drop out.

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

Khanna seemed to suggest that Jackson, who recently finished third in Maine’s Democratic gubernatorial primary, would be a good candidate to replace Platner on the ballot.

“(Jackson) is someone who has spent his life standing up for these progressive values. The movement is about standing for Medicare for All, opposing foreign wars, and getting money out of politics,” Khanna said in a social media post.

Former Maine Senate President Troy Jackson, right, introduces Graham Platner during a May rally at Thompson’s Point in Portland. (Daryn Slover/Staff Photographer)<?xml version="1.0"?> Purchase this image

End Citizens United, a group looking to end the influence of money in politics, rescinded its endorsement and called on Platner to immediately withdraw from the race.

The group said the allegations in Politico’s story are “profoundly disturbing and disqualifying” and represent conduct that is “fundamentally inconsistent from the standards we expect from the candidates we support.”

“No candidate, elected official, or political party is exempt from accountability,” the group’s president, Tiffany Muller, said in a written statement.

Planned Parenthood Action Fund also rescinded its support.

“The accusations against Graham Platner are damning and Platner’s failure to address them or Jenny Racicot directly is disqualifying,” Alexis McGill Johnson, the group’s CEO, said in a statement. “While Planned Parenthood Action Fund remains committed to protecting access to care for Mainers and all Americans, we also unequivocally believe women.”

Hannah Pingree, Maine’s Democratic nominee for governor, said Platner should “exit the race immediately.”

Maine’s legislative leaders also called on Platner to drop out.

Senate President Mattie Daughtry, D-Brunswick, said that Maine Democrats deserve a nominee “with the dignity, judgment and personal character.”

“Survivors deserve to be believed, supported and protected,” Daughtry said in a written statement. “Over the last month, multiple women have come forward with serious allegations against Graham Platner. I stand with each of them and with any survivor who has endured an experience like this. Sexual violence has absolutely no place in our society, and it cannot be tolerated from those seeking our highest positions of power.”

Speaker of the House Ryan Fecteau, D-Biddeford, echoed those remarks, saying Platner needs to step aside so the movement he has built since entering the race last August can continue.

Sen. Bernie Sanders of Vermont had been an early and vocal backer of Platner. He did not respond to a request for comment on Politico’s story and on whether he continues to support him.

Staff Writer Drew Johnson contributed to this story.