New Hampshire has its Senate matchup, and it is already being treated as a fight that could help decide control of the chamber.
Democratic Rep. Chris Pappas defeated progressive challenger Karishma Manzur in Tuesday’s primary, while former Republican Sen. John E. Sununu easily turned back former Massachusetts Sen. Scott Brown.
With most votes counted, Pappas led Manzur about 65% to 33%, and Sununu led Brown about 68.5% to 26.7%.
The result sets up a November contest for the seat being vacated by retiring Democratic Sen. Jeanne Shaheen. National political coverage has framed it as a toss-up and a race Democrats need to hold if they want any plausible path to Senate control.
Kalshi traders, however, are not pricing it that way.
With nearly $400,000 traded, the platform prices Democrats’ chance of holding the seat at 84%.
That is a striking gap between the political narrative, an open-seat brawl in a closely divided state, and the current prediction-market view.
The primary ends the progressive threat
Pappas’ victory was decisive, even if the primary was closer than Democratic leaders once expected.
Manzur, a scientist and Democratic Socialists of America member, tried to build on the anti-establishment, anti-incumbent energy that has lifted progressive candidates in Democratic primaries around the country. Her campaign emphasized Medicare for All, affordability and opposition to U.S. support for Israel’s war in Gaza.
The broader progressive wave had reached New Hampshire’s doorstep. In nearby Maine, left-wing insurgents and anti-establishment candidates have also benefited from an electorate more open to challenging establishment Democrats, especially on affordability and foreign policy.
But Pappas held the line.
The four-term congressman entered with support from Shaheen, national Democratic figures, and a massive financial advantage. By late August, his campaign had raised more than $15 million, compared with less than $500,000 for Manzur.
Manzur had narrowed Pappas’ once-enormous lead. A University of New Hampshire Survey Center poll in late August showed Pappas ahead 47% to 34%, down from a 43-point advantage in January.
But she did not produce the kind of upset that has reshaped Democratic politics elsewhere. The primary instead gave Democrats the nominee they believed was best positioned for a difficult statewide general election: a known quantity with four terms in Congress, a moderate profile and a track record of holding New Hampshire’s competitive First District.
Sununu gets the matchup he wanted
Sununu’s win was even less dramatic.
President Donald Trump endorsed the former senator, who defeated Brown by more than 40 points. Brown, a former Massachusetts senator and Trump administration ambassador, never turned the race into a serious contest.
The result gives Republicans a candidate with a familiar New Hampshire name, statewide experience and a profile that may fit a state that has often rewarded pragmatic Republicans. Sununu previously held this Senate seat from 2003 until Shaheen defeated him in 2008.
That history helps explain why national Republicans see the race as one of their best pickup opportunities. This is not a long-shot challenge against an entrenched Democratic incumbent. Shaheen’s retirement created an open seat, and a late-August UNH poll had Sununu narrowly ahead of Pappas, 45% to 43%.
The parties are already treating it accordingly. Senate Leadership Fund, the GOP-aligned super PAC, has committed $17 million to the general election, while Senate Majority PAC, the Democratic counterpart, had planned $10.2 million in television advertising.
Why Kalshi sees a different race
The 84% Democratic price is not an election result. It is a market estimate that reflects traders’ willingness to buy and sell contracts at current prices. Polymarket, on approximately $100,000 in volume, also has Pappas at 84%.
Still, it is a remarkably confident estimate for a race that polling and party spending suggest is close.
There are a few potential explanations. Traders may be putting more weight on New Hampshire’s recent Democratic lean in federal races, Pappas’ ability to survive in a swing House district, and the possibility that a Trump-endorsed Republican faces a harder statewide electorate than the primary results suggest.
They may also be discounting a single poll showing Sununu ahead, particularly this far from November.
A Senate-control race
New Hampshire matters because Democrats have little room for error.
Republicans currently hold the Senate majority, and Democrats need a net gain of four seats to take control. Their original path depended on holding open or vulnerable Democratic seats in Michigan, Georgia and New Hampshire while flipping Republican-held seats such as Alaska, Maine, North Carolina and Ohio.
That is a difficult map.
Michigan is already proving complicated after progressive candidate Abdul El-Sayed won the Democratic nomination after a costly, divisive primary. Georgia remains one of the country’s central battlegrounds, but Democratic incumbent Sen. Jon Ossoff is leading in all metrics. New Hampshire, meanwhile, is the kind of state Democrats believe they should be able to hold, but cannot afford to lose.
A Democratic loss here would not automatically end the party’s hopes. But it would force Democrats to find another pickup somewhere else, likely in a state that is no easier and may be much harder.
That is why Tuesday mattered. Pappas avoided a progressive-primary upset, Sununu emerged with a clear mandate from Republican voters, and New Hampshire now becomes a full-scale general-election battleground.
