Graham Platner, the Democratic nominee for Senate from Maine, faced extraordinary pressure on Monday from within his party to withdraw from one of the highest-stakes elections in the country after a woman accused him of rape.
Mr. Platner denied the accusation, which was published on Monday in Politico, but said he was taking time to “reflect” on his political path forward. But party leaders had run out of patience after the latest revelation about Mr. Platner, an oyster farmer and first-time candidate.
The Maine Democratic Party, Senator Chuck Schumer of New York, the minority leader, and a host of top Democrats nationwide called on Mr. Platner to step aside.
But as of Monday evening, he had not made a decision on whether to drop out, according to a person familiar with the campaign’s internal discussions, but was weighing his terms of a withdrawal if he decided to do so. He was seeking a guarantee that party officials would replace him with someone who shares “the values and vision and policy agenda” he had advocated, the person said.
Many Democratic heavyweights had stood by Mr. Platner through a series of controversies that marred his primary campaign this year, including a tattoo resembling a Nazi symbol, a history of inflammatory posts online, and a New York Times report detailing that women he had dated recounted him acting in disturbing ways.
But by Monday evening, he had lost almost all of his allies — the congressman who campaigned with him after the first wave of accusations of misconduct, a senator whose endorsement had propelled him through the primary, the liberal podcasters who had previously helped prop him up, and party leadership in Congress and in his own state.
The report on Monday was the first to accuse Mr. Platner of rape. Jenny Racicot, who said she had dated him casually off and on between 2019 and 2021, told Politico that Mr. Platner had sex with her against her will.
The Senate Democrats’ campaign arm, which opposed Mr. Platner in the primary, swiftly vowed to cut off funds for Maine if Mr. Platner remained on the ballot — functionally ending his chances of winning the race.
The leadership of the Maine Democratic Party, which would decide Mr. Platner’s replacement if he withdraws, cited “serious, credible allegations” from multiple women in calling to him to drop out.
The most significant Platner supporter who had yet to weigh in on his status by Monday evening was Senator Bernie Sanders of Vermont, who offered crucial early support to Mr. Platner.
Mr. Sanders said nothing about the candidate on social media after the allegation surfaced. His staff did not answer calls or respond to messages.
Mr. Platner’s other prominent progressive champion, Senator Elizabeth Warren of Massachusetts, turned on him.
On Monday evening, she said he should “step aside as the Democratic nominee and address these serious allegations outside the Senate race.”
Representative Ro Khanna, a California Democrat who has been one of Mr. Platner’s most vocal supporters, also called on the candidate to withdraw.
“I’ve been very clear that sexual assault or violence against women is a red line,” said Mr. Khanna said. “These allegations are very serious and credible. Graham Platner should drop out from the race. I am withdrawing my endorsement.”
In Ellsworth, Maine, Mr. Platner’s campaign headquarters was closed for the evening. In town, few residents seemed to have heard about his latest controversy.
Senator Ruben Gallego, Democrat of Arizona, said in a social media post that he was “rescinding my endorsement” of Mr. Platner, calling the allegations against him “troubling and deeply serious.” He stopped short of calling for the candidate to resign. (Mr. Gallego has faced criticism for his endorsement of former Representative Eric Swalwell, the California Democrat who resigned from Congress and ended his campaign for governor in the face of allegations of sexual assault.)
Senator Susan Collins, the Republican incumbent Mr. Platner is challenging, said in a statement that the “allegations are appalling.” But she added, “It is not up to me to choose the Democratic nominee for Senate.”
Mr. Platner has until July 13 to drop out of the race. If he does withdraw, the state Democratic Party has until July 27 to replace him on the ticket, according to Maine law.
Reid J. Epstein, Murray Carpenter and Lisa Lerer contributed reporting.
