Nearly all polls have closed in Michigan, where voters were helping decide which Republican candidate they would like to see go up against President Barack Obama in the fall.
Most polling precincts closed at 8 p.m. EST Tuesday in a primary election that polls suggested was a tight race between Michigan native son and ex-Massachusetts Gov. Mitt Romney and ex-Pennsylvania U.S. Sen. Rick Santorum. The ballot also includes Newt Gingrich and Ron Paul.
Losing the state he grew up in would be a blow to Romney, but Santorum was banking big on a strong showing in Michigan for momentum heading into next week's Super Tuesday contests.
Obama has no competition in the Democratic primary, and votes for him won't count.
Polls close an hour later in parts of upper Michigan.