In New Hampshire, Democratic Rep. Paul Hodes is unopposed for the Senate nomination.
But Republicans are settling a multi-candidate race.
The front-runner, former Attorney General Kelly Ayotte, campaigned with the support of the Republican party establishment and Sarah Palin. But Ovide Lamontagne claimed backing from tea party activists.
Bill Binnie and Jim Bender campaigned on the strength of their records as businessmen.
Republicans have spent more than $9.5 million trying to retain the seat of retiring U.S. Sen. Judd Gregg –believing the winner of the primary will have an edge in November.
Ayotte has spent $2 million to push a conservative anti-Democrat, anti-federal spending agenda.
Multimillionaire businessman Bill Binnie has spent more than $6 million – including more than $5 million out of his own pocket – but political analysts believe Binnie hurt himself with television ads criticizing Ayotte too early. Ayotte may have hurt herself by responding.