Along with creating tumult in a must-win race for Democrats, Graham Platner's exit is laying bare division between the party's left wing and moderates.

Graham Platner's meteoric rise from relative obscurity to the Democratic nominee in this year's marquee US Senate contest has now ended in catastrophic collapse. The oysterman and former Marine who bested a popular governor and built a grass-roots network of more than 15,000 supporters in Maine announced he was suspending his campaign on Wednesday night. The news came via recorded video posted on social media, just a little more than 48 hours after Politico published a story containing allegations from an ex-girlfriend that an intoxicated Platner had entered her home uninvited in 2021 and allegedly sexually assaulted her. He has denied the allegation. "We went toe to toe with one of the most entrenched political systems in the history of the world, and we won," Platner said in his 11-minute video announcing the end of his campaign. "And now they are not going to let us have it, not if it's me." Platner, who had been championed by liberal stalwarts like Vermont Senator Bernie Sanders and Massachusetts Senator Elizabeth Warren, was his party's chosen challenger to unseat five-term Senator Susan Collins – the only Republican in Congress representing a state that Democrats won in the 2024 presidential election. To take control of the Senate in November's midterm elections, they have to flip four Republican-held seats while defending all of theirs. Maine is widely considered a must-win target. Now, Platner's exit is threatening to deal a serious blow to their hopes. It is also re-exposing rifts between the party's left wing and moderates that could not only endanger their success this year but in the 2028 presidential race as well. The sexual assault allegation against Platner was just the latest, most serious, controversy to dog the novice candidate since he entered the race last August.