Graham Platner, the Democratic nominee for the US Senate seat in Maine, officially withdrew his candidacy on Friday after submitting the required paperwork to the Maine secretary of state's office, bringing a turbulent campaign to a close. The formal withdrawal came two days after Platner announced on social media that he would exit the race, following a sexual assault allegation he has denied. Maine state party executive director Devon Murphy-Anderson said the allegations were "very real and very credible."

In a letter accompanying his withdrawal — which he also posted on social media — Platner made no mention of the allegations, instead invoking the populist themes that had fuelled his rapid rise. Citing the more than 156,000 votes he received in the 9 June primary, he called for "a new kind of politics" free from "billionaires, oligarchs, or the political establishment" and pledged to continue the movement built around his campaign. Platner had drawn notable backing from progressive figures including Vermont Senator Bernie Sanders and California Representative Ro Khanna. In an earlier video posted Wednesday, he denied the allegations outright, claiming the Democratic establishment was using them to undermine his campaign.

The sexual assault allegation was the latest in a series of controversies that shadowed Platner's candidacy. Old social media posts containing racist, sexist, and homophobic language resurfaced during the campaign, which he attributed to struggles with PTSD, and he faced questions about a since-removed tattoo on his chest that resembled a Nazi emblem. Despite these revelations, his political support held until the assault allegation proved insurmountable for the party.

With Platner out, Maine Democrats face an urgent scramble to name a replacement before the 27 July deadline to finalise the November ballot. State law allows the party to select a new nominee through a nominating convention, which more than 100 state party committee members had already voted to authorise. Among those who have announced runs for the nomination are former Maine state senator Troy Jackson, Maine secretary of state Shenna Bellows, and Nirav Shah, former director of the Maine Center for Disease Control and Prevention, all of whom lost bids for the governor's nomination in June. Several other candidates have also entered contention.

The stakes are high: Maine is considered a critical state for Democrats seeking to gain control of the narrowly divided Senate. The eventual nominee will face five-term Republican incumbent Susan Collins, widely regarded as one of the most formidable electoral opponents in the country. Political analysts warn that whoever emerges from the convention will need unified party support to stand a realistic chance — and that the Platner episode underscores a broader lesson about vetting candidates for character and judgment, not simply ideological alignment.