For sixteen years, New Hampshire has returned Democrats to the Senate with quiet consistency — a streak that once felt like settled geography. Now, with Chris Pappas preparing to face John E. Sununu, a Republican whose name is woven into the state's political fabric, that certainty is giving way to something older and more honest: the recognition that no political inheritance is permanent. What happens in this small New England state may tell us something larger about where the country is heading.