Troy Matteson finished at 10-under-par 270 to take second place for the second week in a row. Third-round leader Camilo Villegas carded a 1-over 71 in the final round to share third place with Danny Ellis, David Hearn and Aaron Barber at 9-under-par 271.
Couch was five shots behind Villegas to start the final round at Hardscrabble Country Club, but he was on a roll early. He carded back-to-back birdies from the par-3 second and three consecutive birdies starting at the par-4 fifth.
The 32-year-old hit his second shot to 4 feet for a birdie at the par-4 10th and reached the green in two at the par-5 11th. Couch missed his eagle try, but he was left with a short putt for birdie and easily converted.
Couch stumbled to a bogey at the 12th and hit his drive into a fairway bunker at the par-4 13th. Couch then played his second shot from the sand to 5 feet for a birdie and knocked his approach inside 6 feet for a birdie at the 14th to move to 13 under.
At the par-3 15th, Couch dropped his tee shot within 7 feet of the hole and ran home the birdie putt to make it three straight. Couch followed with pars on his next two holes before rolling in a 22-foot putt for a birdie at the last to match the course record.
'That was something today,' said Couch. 'I fought back hard yesterday. I was proud of myself yesterday. Got it back to even par and gave myself a chance today, which I ended up taking advantage of.'
Matteson picked up a birdie at the third and tallied an eagle at the par-5 sixth to jump to 10 under. At the par-4 10th, Matteson landed his second shot inside 6 feet and converted the putt to grab a share of the lead.
The 25-year-old was unable to keep up with Couch, however, and found trouble with a bogey at the 13th. Matteson parred his way in for a round of 67.
'I had some chances and I just didn't take advantage of them,' said Matteson, who moved into first place on the Nationwide Tour money list. 'That's going to happen out here. All in all it was a solid round.'
Villegas had a solid start with a birdie at the third and sank an 18-foot birdie putt at the sixth to maintain his lead at 12 under. The Colombian struggled to a bogey at the eighth, however, and collected a pair of bogeys on the back nine to finish six shots back.
Jason Schultz bogeyed the closing hole to finish alone in seventh place at 8-under-par 272 after a round of 71. Fran Quinn, Jeff Gove, Mike Springer, Kyle Thompson and Tjaart van der Walt followed at 6-under-par 274.