Who will win the 2026 U.S. Senate election in New Hampshire — Democrat Chris Pappas or Republican John Sununu?

Polymarket's exact-question contract prints Democrat at 85 cents, Republican at 17. I'd normally just take that number, but total volume here is $38k - thin next to a race this nationally watched, and Kalshi lists the same contract without a price I could confirm at pull time. A tape this thin can run ahead of the news. I dock it five or six points for liquidity risk and land at 80, favored but not blowout-favored.

Break it into stages. P(Pappas wins the Dem primary) is ~0.97 off a 53-29 lead over Manzur. Conditional on the general-election matchup, P(Sununu is the GOP nominee) is ~0.85 given his 48-19-to-59-20 primary leads and the Trump endorsement; P(Brown nominee) ~0.12. Pappas's polling edge is +3 against Sununu (47-44) but +9 against Brown (48-39), so weight those: 0.85(0.80) + 0.12(0.85) + 0.03(0.75) is about 0.80, times the 0.97 primary factor is about 0.78. I round down slightly for the tightening trend the polling itself shows.

I count what New Hampshire has actually done, not what it's said it will do. Three of the last four top-of-ballot Senate contests went Democratic - but the fourth, the only true open seat in that set, went Republican by sixteen points when Ayotte beat Hodes in 2010. This is that same shape again: no incumbent, a credible GOP nominee, a midterm. And the ledger keeps writing itself past that one race - Harris carried this state by only 2.8 in 2024, less than half of Biden's 7.3, the same day the voters sent a Republican to the governor's chair by 9.3. The venue is drifting redder than the market wants to admit.

Follow the mechanism. Pappas has won NH-1, a genuine swing district, five straight times - he already knows how to build a statewide-adjacent coalition. He carries a 2:1 cash edge into the fall and a Trump approval crater (net -25) that depresses GOP-leaning turnout and energizes his own base. Sununu's route runs through ticket-splitters who backed Ayotte for governor, and those voters exist - but they have to show up twice, once at the top for Sununu against a well-funded, well-known challenger. That's a heavier lift than the coattail-free governor's race Ayotte won. Route favors Pappas, closely.

I read the man, not the tape. Here is a five-term Congressman who has never lost a race in a district Republicans should win, running now for an open seat his own mentor is vacating. Against him: a comeback candidate, seventeen years removed from the Senate, who called Trump 'a loser' in print before turning around to accept his endorsement - a man running as someone he wasn't a decade ago. Voters can smell that seam. Pappas's is the steadier hand, and steadier hands win open seats in states this exhausted with Washington drama.

Everyone's piled onto the 85-cent side, which is exactly where I go looking. The polling trend nobody's pricing: Pappas led by 7 in April, by 3 in late June, and Emerson had it a flat tie back in March - that's not a stable lead, that's a lead in motion, and it's moving the wrong way for the favorite. Sununu is also simply a better candidate than the two men who got blown out here in 2020 and 2022, and Ayotte just showed a real GOP floor in this state nine months ago. I'll take Sununu in the low-to-mid thirties and let the September post-primary polls come to me.

Watch the timing. Trump's approval in this state hits its lowest mark since October 2017 in the very month the general election clock starts running - a coincidence too neat to be one. And watch the man on the other side: Sununu returns to a stage he left in 2009, endorsed by a president he once called a loser, in a state that has spent a decade rewarding candidates who stay who they are. Pappas never had to reinvent himself. The story that keeps its own promises is the one where the steady man wins the seat the storm-tossed one is chasing back.