Elections
For years, Pappas was floated as a potential candidate for the U.S. House of Representatives, the United States Senate, and governor of New Hampshire. After U.S. representative Carol Shea-Porter announced that she would not seek reelection in 2018, Pappas announced his candidacy for her seat in New Hampshire's 1st congressional district. Pappas defeated ten other candidates for the Democratic nomination, including former assistant to the secretary of defense for public affairs Maura Sullivan and Bernie Sanders's son Levi Sanders, with 42.2% of the vote.
Pappas defeated Republican Eddie Edwards, a former police chief and member of the New Hampshire State Division of Liquor Enforcement, in the general election, with 53.6% of the vote. He won every county except Belknap County.
Pappas ran for reelection to a second term and was unopposed in the Democratic primary. He defeated Republican Matt Mowers, a former New Hampshire Republican Party executive director and former U.S. State Department staffer, in the general election, receiving 51.32% of the vote.
Pappas was reelected in 2022. He ran unopposed in the Democratic primary and defeated future Trump administration official Karoline Leavitt with 54% of the vote.
Pappas ran for a fourth term in 2024. He defeated Kevin Rondeau for the Democratic nomination, winning 95.2% of the vote. He faced Republican Russell Prescott, a former state senator with whom Pappas served on the New Hampshire Executive Council, in the general election. He was reelected by 32,641 votes.
In September 2026, Pappas sought the Democratic nomination for the U.S. Senate seat being vacated by Jeanne Shaheen. He faced scientist Karishma Manzur in the Democratic primary. Pappas entered the primary as the frontrunner and had been endorsed by Shaheen.
