'I was lucky to have good speed on my putts today,' said Gore, who earned $94,500 for the win. 'I didn't have a lot of 6- and 7-footers coming back. I think that was the key today to keeping things stress-free.'
With the back-to-back wins, Gore is the first player in Nationwide Tour history to win consecutive events twice in a career. He also did it in 2002 when he won the Oregon Classic and the Boise Open.
Bill Haas also closed with a 67 to take second place at 10-under-par 270.
Jason Dufner, who started the round in second place, stumbled to a 4-over 74 and fell into a tie for third place. He was joined at 6-under-par 274 by Jon Mills (71) and Matt Bettencourt (69).
Gore, who moved into the spotlight with his stellar play in the third round of the U.S. Open, opened with a birdie at the first. Dufner moved ahead of Gore at minus-13 as he opened with three straight birdies.
The 31-year-old Gore climbed back into a tie for the lead with Dufner when he birdied the fourth. Gore took control with back-to-back birdies from the seventh.
As Dufner was tumbling down the leaderboard, Gore did not do much better. He faltered to a bogey on the 11th and another on No. 14 at Troy Burne Golf Club.
Gore moved back to minus-14 as he rolled in a lengthy birdie try on the par- five 16th. He closed with a pair of pars to secure his second win of the season.
'If I hadn't shot 84 in the Open then maybe I wouldn't be sitting here today,' said Gore. 'Sunday golf is a lot more interesting than Thursday through Saturday golf. I surprised myself after Sunday at Pinehurst. That could have been a make-or-break round for me. To be honest, the last six weeks have been pretty incredible. I don't know how to explain it.'
One more win this season for Gore would give him the Battlefield promotion. That is an automatic promotion to the PGA Tour.
'It's pretty cool, isn't it?' said Gore of his chances of returning to the tour. 'This was the most important event of the year for me. I've just got to keep my focus. I am going to take a couple of weeks off, chill out and then try to come out firing.'
Haas flew up the leaderboard early on. He birdied the first, then sank three straight birdie tries from the third to move to 11-under. He got to 12-under with a birdie on the 10th. However, Haas stumbled to bogeys on 14 and 17.
'It would have been nice to finish 11- or 12-under to give Gore something to think about,' said Haas. 'Maybe that would have changed something with Jason. You're always disappointed when you don't win, but this is my best finish so I can't be too disappointed. I still need to win though.'
Eric Axley jumped into a tie for sixth place with a 5-under 65, the low round of the day. He was joined at 5-under-par 275 with Chris Tidland (68) and Steve LeBrun (74).
Steven Bowditch, Charley Hoffman, Andy Morse and Dicky Pride finished one stroke further back at minus-4.