Republican Sen. Richard Lugar, the face of Indiana politics for nearly four decades, is battling for political survival against a tea party-backed GOP challenger in the state's primary. It is the highest-profile contest in four states with voting Tuesday.

Mitt Romney is expected to coast to victory in primaries in Indiana, West Virginia and North Carolina as he continues his quest for the GOP presidential nomination.

Wisconsin Democrats are preparing to pick a candidate to run against Republican Gov. Scott Walker in just the third gubernatorial recall election in U.S. history.

In North Carolina, voters are considering a referendum that would effectively ban same-sex marriages.