Former Maine Senate President Troy Jackson has emerged as the clear frontrunner to become the Democratic nominee in Maine's US Senate race, after winning the overwhelming majority of delegates in a hastily arranged selection process. He stepped into contention following the withdrawal of Graham Platner, whose candidacy had run into difficulties, leaving Jackson well placed to take on veteran Republican Senator Susan Collins in what is shaping up to be one of the most closely watched contests of the cycle.

Delegates backing Jackson secured more than 90% of the 319 slots contested, putting him far ahead of his rivals for the nomination. The race has already drawn national attention, with at least one independent voter telling broadcasters they would back Collins over Jackson, underlining the challenge Democrats face in unseating the long-serving senator in a state with a strong independent streak.