Caucuses predict the actual winner less than two-thirds of the time.
Two reasons: More Republicans in the sample, and better support for Brown in his base.
The Texas senator takes his show on the road to the Granite State.
The possible 2016 presidential candidate is carving out a big presence in the earky nominating states.
The new NBC/Marist College polls suggest some swing states haven't trended toward Obama in recent weeks.
The matchup is expected to be one of the top governor's races in the country.