Republican Senator Susan Collins of Maine faces a genuinely competitive re-election battle in 2026 after Democrats replaced their nominee, with new polling and Fox News's Power Rankings both rating the contest a toss-up. Collins, a long-serving incumbent, will now face Troy Jackson rather than the party's original candidate, in a race widely seen as pivotal to control of the Senate.

Jackson has stepped in for Graham Platner, who had originally secured the Democratic nomination before the party's shake-up prompted his replacement. The Fox News Power Rankings, which assess how competitive Senate contests are nationwide, place Maine among the chamber's most closely watched battlegrounds heading into the midterms, underscoring the state's outsized importance to both parties' hopes of a Senate majority.