The 2026 U.S. Senate election in Maine is emerging as a potential battleground where Republicans could face a challenge to their lone New England seat. Incumbent Senator Susan Collins, a moderate Republican seeking a sixth term, plans to run again, but her position is complicated by Maine’s Democratic lean and the state’s history of competitive races. With Republicans holding a 53-47 Senate majority, including two independents caucusing with Democrats, this race offers Democrats a rare opportunity to flip a seat in a state Kamala Harris carried by seven points in 2024. The prospects for a party change hinge on candidate strength and national trends, though Collins’ track record suggests resilience against the odds.
Collins, first elected in 1996, has defied Maine’s blue tilt by cultivating a moderate image, winning re-election in 2020 with 51% against a strong Democratic challenger. Her seat is the only Republican-held one up in a Harris-won state in 2026, making it a focal point for Democrats eager to narrow the GOP’s Senate edge. Recent polling shows her favorability at 49%, with 45% unfavorable, a net positive of 4%, reflecting a slight recovery from earlier surveys where 71% of respondents questioned her re-election. However, her age—72—and her occasional clashes with Trump, including votes against some of his nominees, could alienate conservative voters in a Republican primary, where former police officer Dan Smeriglio has already emerged as a challenger. National Republicans back Collins, but her swing-vote status may test party unity.
On the Democratic side, the field remains fluid as candidates weigh their options. Term-limited Governor Janet Mills, 77, has not ruled out a run but faces age-related concerns, while Representative Jared Golden, 42, a centrist from a Trump-leaning district, is a potential contender. Golden’s past role as a Collins staffer and his neutral stance in her last race complicate his candidacy, though his statewide appeal could challenge her moderate base. Other possibilities include Representative Chellie Pingree and Jordan Wood, a Lewiston native and former congressional aide, who has already announced his campaign. A University of New Hampshire poll from May suggests Mills is the preferred Democratic challenger, with 47% favorability, but no candidate has solidified support.
The prospects for a party change lean toward Democrats if they field a strong nominee and capitalize on mid-term dynamics often unfavorable to the president’s party—here, Republicans under Trump. Maine’s Cook Partisan Voting Index shows a slight Democratic edge, and the state has backed Democratic presidential candidates since 1992. Yet, Collins’ history of overperformance, including narrow wins in Democratic-leaning cycles, tempers optimism. The race is rated “Tossup” by some analysts, reflecting its competitiveness, though her incumbency and fundraising advantage—bolstered by her Appropriations Committee chairmanship—pose hurdles. Rural voter discontent with economic issues could bolster Collins, but urban turnout in Portland and Bangor may favor Democrats.
This race tests the limits of moderation in a polarized era. Collins’ ability to retain independent voters, who often decide Maine elections, will be key, but a unified Democratic challenge could exploit her vulnerabilities, especially if Trump’s policies alienate moderates. Without current head-to-head polling, the outcome remains uncertain, resting on candidate recruitment and national sentiment by November 2026. For now, the seat teeters on a knife-edge, with the GOP’s hold contingent on Collins’ enduring appeal and the Democrats’ ability to seize a rare opportunity.