The open Senate seat following Jeanne Shaheen’s retirement and the closely contested general election matchup between Democratic frontrunner Chris Pappas and leading Republican John Sununu have produced high uncertainty in expected voter participation for the November 3 contest. Recent polling shows a narrow race that could spur strong get-out-the-vote efforts from both parties, while the September 8 primaries may clarify candidate appeal and enthusiasm levels. New Hampshire’s history of variable midterm turnout, combined with national political conditions and potential late-cycle factors such as weather or campaign spending, leaves traders assigning similar probabilities across turnout ranges from under 500,000 to 800,000-plus votes.