New Hampshire voters go to the polls on Tuesday to choose Democratic and Republican Senate nominees, in a contest that could help decide control of the chamber in the midterm elections. On the Democratic side, socialist-aligned first-time candidate Karishma Manzur is mounting a late surge against establishment favourite Rep. Chris Pappas, mirroring a broader pattern this primary season of insurgent left-wing candidates challenging centrists. The eventual Democratic nominee will face the winner of a competing Republican primary between two former senators, John E. Sununu and Scott Brown, for the seat being vacated by retiring Democratic Sen. Jeanne Shaheen.

Manzur, a biochemistry PhD and Democratic Socialists of America member, is campaigning on universal healthcare, a $20 minimum wage, abolishing ICE and ending military aid to Israel, accusing Pappas of being a "genocide enabler" over his AIPAC-linked support. Pappas, a four-term congressman with strong union and establishment backing, has defended his record on Israel and campaign finance reform, arguing he appeals to moderate voters across the political spectrum. Republicans, who have not won a New Hampshire Senate race in 16 years, see the open seat as a key opportunity to bolster their slim Senate majority.