Former U.S. Senator John Sununu won New Hampshire’s Republican primary on Tuesday, advancing to face Democrat Chris Pappas in November’s general election for the state’s open Senate seat. Sununu defeated former Massachusetts Senator Scott Brown in the GOP primary, securing the Republican nomination in a race for the seat being vacated by retiring Democratic Senator Jeanne Shaheen.
On the Democratic side, U.S. Representative Chris Pappas won his party’s nomination, fending off a challenge from progressive candidate Karishma Manzur. Both winners emerged from primaries held September 8, setting up what political analysts view as one of the year’s most competitive Senate races.
Sununu, who represented New Hampshire in the Senate from 2003 to 2009, has positioned himself as a candidate with executive experience and deep state roots. Trump endorsed Sununu in February 2026, backing him over Brown despite Sununu’s past criticism of the president. The endorsement proved significant in the GOP primary, where Sununu led in most pre-election polling.
Pappas, who has served in the U.S. House since 2019 representing New Hampshire’s 1st congressional district, will be the first out LGBTQ+ man elected to the U.S. Senate if he prevails in November. He campaigned as a moderate Democrat focused on kitchen-table issues, contrasting his message with Manzur’s more progressive platform.
The November matchup arrives as New Hampshire has not elected a Republican to the Senate since 2010, when Kelly Ayotte won. However, recent polling showed the race in a statistical tie, with Republican operatives citing an Emerson College survey indicating near-parity between the candidates. Outside spending is expected to exceed $30 million, underscoring the seat’s strategic importance to both parties in a chamber where Republicans currently hold a 53-45 majority.
Shaheen’s retirement opened this seat after she served three terms. Her exit, announced in March 2025, triggered competitive primaries on both sides, with both parties viewing the race as a genuine toss-up headed into the general election. The winner will inherit a seat that has alternated party control in recent decades, reflecting New Hampshire’s status as a true swing state in Senate races.
Sources
- NBC News — Confirmed Sununu’s Republican primary victory and Pappas’s Democratic primary win on September 8, 2026
- The Guardian — Reported Trump-backed Sununu triumphed over Scott Brown in the Republican primary
- CNN — Documented Sununu and Pappas as the nominees for their respective parties in the general election
- New York Times — Provided context on Pappas as the presumed Democratic nominee and the race as competitive
- Politico — Reported Trump’s endorsement of Sununu in February 2026
- RealClearPolitics — Showed polling data with Pappas leading by 2 points in general election averages
- NBC Boston — Confirmed Sununu’s prior Senate service from 2003 to 2009
- USA Today — Noted the $30 million in outside spending expected in the race
