Republican governors in Florida, Michigan and Wisconsin fended off Democratic challengers on Tuesday in three of the most disputed contests among three dozen races that revolved heavily around voters' concerns about the uneven economic recovery.
Wisconsin Republican Governor Scott Walker, the projected winner over Democrat Mary Burke, is a conservative Tea Party favorite considered to have presidential aspirations.
He survived a recall election in 2012, beating back a labor-backed effort to oust him from the governor's office.
In Florida, Republican Governor Rick Scott was the projected winner over Charlie Crist, a former Republican governor turned Democrat. Both Florida candidates struggled with low popularity during the contest that featured months of attack ads on both sides.
Michigan Governor Rick Snyder prevailed over a Democratic political insider, former U.S. Representative Mark Schauer, NBC projected.
The three big wins for Republican incumbents add to what is shaping up to be a good night for Republicans across the country, with the party on the cusp of winning back control of the Senate.
Voters disgruntled over the uncertain economic recovery were showing an anti-incumbent sentiment, and several sitting governors struggled to defend their fiscal policies in their re-election bids.
In Pennsylvania, Republican Governor Tom Corbett lost to Democrat Tom Wolf, according to a projection from Reuters/Ipsos, making him the first incumbent governor in modern state history to fail to win a second term.
Incumbents were locked in tight races in Connecticut, Alaska, Colorado, Kansas and Illinois.
In several races where outcomes were as expected, Republican Governor Nikki Haley was the projected winner in South Carolina, Republican Governor John Kasich was the projected winner in Ohio and Republican Governor Bill Haslam was the projected winner in Tennessee.
Democratic Governor Andrew Cuomo was the projected winner in New York, and Republican Governor Robert Bentley was the projected winner in Alabama.
In Texas, Reuters/Ipsos projected Republican Greg Abbott, the state's attorney general, defeated his Democratic opponent, state Senator Wendy Davis.
Reuters/Ipsos projected Nebraska Republican Pete Ricketts, a co-owner of the Chicago Cubs, as the winner over Democrat Chuck Hassebrook.
As expected, incumbent Republican Governor Mary Fallin was the projected winner in Oklahoma, as was sitting Republican Governor Matt Mead in Wyoming.