'My confidence level is high,' said Bates. 'Hopefully I can finish things off tomorrow.'
Michael Long finished alone in third place at 6-under-par 207 after a round of 68. Kenneth Staton fired a 64 and was one shot further back along with Kevin Durkin and Doug Barron at 5-under-par 208.
Bates, whose lone Nationwide Tour victory came at the 1997 Wichita Open, got off to a quick start with a birdie at the first and added back-to-back birdies starting at the par-four fourth to reach 6 under.
The 43-year-old faltered to a bogey at the eighth but came back to birdie his next two holes.
Bates, who tied for eighth at the First Tee Arkansas Classic in April, closed with a birdie at the 17th to secure the 54-hole lead at a Nationwide Tour event for the first time since the 1995 Texarkana Open.
'I've been playing good. There's no secret to it, just a lot of fairways and greens,' said Bates. 'It seems like everybody who wins seems to get good breaks and I've been getting good breaks this week. When I have hit in the rough, which isn't too often, I've been fortunate enough to get good lies. Hopefully it will continue tomorrow.'
Gow, who shared the 36-hole lead with John Morse, jumped out of the gate with an eagle at the first but tallied three bogeys on the front nine to fall back to 5 under around the turn.
The Australian picked up another eagle at the par-5 14th to finish one shot back at 7-under-par 206.
'They key word is probably surviving,' said Gow, who posted a 70 on Saturday. 'It's difficult to lead a golf tournament and take it all the way through. I had to call on every part of my game just to keep getting out of every hole.'
Mike Springer and Nick Watney finished four shots off the pace at 4-under-par 209. First-round leader Jason Caron, Scott Sterling and Kyle Gallo followed at 3-under-par 210.
Morse, who stood atop the leaderboard with Gow after the second round, managed a 77 on Saturday to finish in a group at even-par 213.