"Maine’s 1-term Dem Gov. Janet Mills will run for Senate seat held by Susan Collins next year.. setting up a potential matchup between the parties’ best-known figures in a state where Democrats see a chance to gain a seat"

AP News

Maine Gov. Janet Mills will challenge Sen. Susan Collins in key 2026 Senate contest, AP sources say

Maine’s two-term Democratic Gov. Janet Mills will run for the U.S. Senate seat held by veteran Republican Sen. Susan Collins next year.