Troy Jackson, a former Maine lawmaker and fifth-generation logger from the North Maine Woods, has emerged as the likely new replacement for the state’s Democratic Senate nominee after former candidate Graham Platner quit the high-stakes race less than two weeks ago.Platner’s departure followed a sexual assault allegation that he denied but forced his exit anyway. It sparked a wave of potential candidates eager to prove to Mainers that they could take on longtime Republican Sen. Susan Collins.But by Sunday, the field had largely been cleared after Jackson supporters spent the weekend securing hundreds of delegates who promised to back him at the upcoming state convention. Under a never-before-used system to replace Platner, delegates will vote Saturday in Bangor on a new Senate nominee. Out of the 601 delegates who will gather this weekend, Jackson’s campaign says they have 481 delegates committed to supporting him. Top opponents — ranging from Secretary of State Shenna Bellows to Nirav Shah, former director of Maine’s Center for Disease Control and Prevention — have since dropped out, while Jackson announced Monday that he was focusing his attention on ousting Collins. “I’m grateful to Democrats across Maine for putting their faith in me and in what we’re fighting for,” Jackson said in a statement. “This didn’t happen because of one person. It happened because hundreds of volunteers put in the hours, knocked on doors, made phone calls, and believed we could build something bigger than ourselves.”