President Trump told the Justice Department to intervene in the race, where polling shows Republicans at risk of losing a seat.

© Kerry Tasker/Reuters

Chris Pappas, the Democratic nominee in New Hampshire, would make history if he won. On the campaign trail, he doesn’t dwell on it.

© John Tully for The New York Times

The Republican incumbent, Roger Marshall, is facing a surprisingly tough challenge from the Democratic nominee, Adam Hamilton.

© Pool photo by Charlie Riedel