In the small but consequential state of New Hampshire, John E. Sununu has emerged from a contested Republican primary to challenge long-serving Democratic Senator Jeanne Shaheen — a matchup that carries weight far beyond its borders. The outcome of this general election may well determine which party holds the balance of power in the U.S. Senate, making it one of those rare local contests that becomes a mirror for the nation's broader political soul. Both candidates carry distinct visions and political legacies into a race where independent voters, as so often in American democracy, may hold t