New Hampshire's Senate race has taken shape ahead of November's US midterm elections, with Democratic Congressman Chris Pappas set to face Republican John E. Sununu, a former one-term senator, for the seat being vacated by retiring Democrat Jeanne Shaheen. The contest is significant because Republicans have not held a New Hampshire Senate seat in 16 years, yet polling shows the race close within the margin of error, making it a potential pick-up opportunity for the GOP as it seeks to offset possible losses elsewhere, such as North Carolina, in a battle where Democrats need to flip four seats to take control of the chamber.

Pappas secured his party's nomination against four rivals, including Karishma Manzur, who was backed by the Democratic Socialists of America, and previously defeated Karoline Leavitt, later White House Press Secretary, in 2022. Sununu, whose family has a long history in New Hampshire politics, beat a Republican field that included former Massachusetts senator Scott Brown to win his nomination. Analysts including the Cook Political Report still rate the seat as leaning Democratic, but the popularity of Republican Governor Kelly Ayotte and the strong electoral track record of the Sununu name have made the contest tighter than expected, with a significant proportion of voters undecided.