BOSTON — Massachusetts Sen. Ed Markey publicly cut Graham Platner loose Monday night — pulling his backing from the Bernie Sanders-endorsed Marine veteran who won Maine's Democratic Senate primary in a landslide and now faces a sexual assault allegation from a former girlfriend.

Platner, a 41-year-old oyster farmer and eight-year Marine Corps veteran with three combat tours in Iraq and one in Afghanistan, won the June Democratic primary in Maine with 72% of the vote. He ran as an anti-establishment populist, backed by Sen. Bernie Sanders and organized labor, against incumbent Republican Sen. Susan Collins.

Politico first reported the allegation Monday. Jenny Racicot, a 41-year-old Maine woman who had an on-and-off relationship with Platner for more than two years ending in 2021, told the outlet that Platner showed up at her home in 2021 — drunk and uninvited — and forced himself on her while she was on the couch. Platner denies the account and called it "categorically false."

The Politico report followed a June New York Times story in which three other women who had dated Platner described his behavior as "unsettling," "demeaning," and in one case "physically threatening."

Markey joined a cascade of Democratic officials who publicly cut Platner loose Monday. Senate Minority Leader Chuck Schumer and Sen. Kirsten Gillibrand issued a joint statement demanding "Graham Platner needs to immediately withdraw as the Democratic nominee for Senate and allow Maine Democrats the opportunity to choose a new candidate who can defeat Susan Collins." Rep. Ro Khanna, one of Platner's earliest and most high-profile congressional endorsers, also pulled his endorsement.

Platner said Monday he was taking "time to reflect on the best path forward" and canceled his campaign events.

The Racicot allegation is the sharpest but not the first controversy to hit Platner's campaign.

Mocking a wounded soldier. Deleted Reddit posts by Platner under the handle "P-Hustle" resurfaced during the campaign. In a 2019 comment on video of Army veteran Teddy Daniels — shot multiple times surviving a Taliban ambush — Platner wrote that Daniels "didn't deserve to live" and that only "poor marksmanship on the Taliban's part" brought him home. In another March 2019 post, Platner called the Army "awful" and "full of fat, lazy trash who would rather not be in uniform." Other resurfaced posts disparaged sexual assault victims and used slurs against multiple groups. Platner said he was "angry, crude and still dealing with trauma" when he wrote them.

Extramarital messaging. The Wall Street Journal reported that Platner exchanged sexually explicit messages with multiple women toward the start of his marriage. The campaign confirmed the reporting.

Platner has attributed the record to a "dark period" of undiagnosed PTSD and heavy drinking. "I've been open about what was a very dark period of my life where I struggled with undiagnosed PTSD, too often self-medicated with alcohol, and was a far from perfect boyfriend," he said.

The DSCC. The Democratic Senatorial Campaign Committee said Monday it will not invest in the Maine Senate race if Platner remains on the ballot.

Under Maine election law, Platner would have to end his candidacy by July 13 for Maine Democrats to nominate a replacement in time for the general election against Collins — a seat Democrats have identified as critical in their bid to retake the Senate.

Sanders, whose endorsement powered Platner's populist ascent, has not publicly commented.