Republican strategists aligned with Donald Trump are privately delighting in the turmoil surrounding Maine's Democratic Senate candidate, Graham Platner, whose campaign has been engulfed by controversy. Platner, a US Marine veteran who won the Democratic primary last month, is now facing a fresh sexual assault allegation and calls from senior Democrats to withdraw, throwing the party's bid to unseat incumbent Republican Susan Collins into disarray. The chaos matters because Maine is one of the most closely watched races heading into the November midterms, and Democratic infighting could hand Republicans an easier path in a seat they had expected to fight hard to defend.

On Monday a woman told Politico that Platner had once forced her to have sex over her objections; his campaign had previously denied the claim and did not respond to a request for comment. Platner had already faced accusations of mistreating women, a covered-up Nazi tattoo and offensive online remarks, prompting figures from Bernie Sanders to Chuck Schumer to urge him to quit. The Democratic Senatorial Campaign Committee has said it will not fund him, leaving him reliant on small-dollar donors unlikely to match the tens of millions expected to be spent on advertising. Democrats have until 13 July for Platner to drop out and 27 July to name a replacement, with Governor Janet Mills and former state senator Troy Jackson floated as alternatives, though Republicans believe Collins would still prevail.