Chris Anderson, Tommy Tolles and Brad Elder are tied for sixth place at 6-under-par 66 at Somerby Golf Club.
Bates, who played on the PGA TOUR two different times in his career, was in the morning wave and tallied four birdies over his opening-nine holes. He birdied the par-5 11th, then went cold.
He made four consecutive pars, but birdied 16 and 18 to post his 65.
'I hit everything really well today,' said Bates, who is playing in his third event this season on the Nationwide Tour. 'The fairways are generous and the course is in fabulous shape. You can make a lot of putts on these greens.'
Turnesa was the only other leader from the morning and started on the 10th tee. He birdied the 10th, then birdied Nos. 13 and 18 to make the turn at minus-3.
Turnesa flew out of the gate on the back nine with four birdies in his first five holes. He parred his last four holes to join Bates in the clubhouse.
'I played great today. I didn't miss a fairway, made seven birdies and zero bogeys,' Turnesa said. 'I'm very happy with where I stand, but it doesn't matter who is leading on Thursday. All that matters is who is leading on Sunday.'
Delsing, also a former member of the PGA TOUR, notched four birdies on his front nine, then birdied the par-3 13th. He bogeyed 14, but birdied three of his last four.
O'Neal, who tied for third here last year, played off the back nine first and had a mix bag of four birdies, an eagle and two bogeys. He made the turn at 4 under par, then recorded three birdies on his second nine to join the lead.
Wood, who got into the event because of a top-25 finish last week, his first made cut on the Nationwide Tour, had only two birdies over his first 11 holes.
Over his final seven holes, Wood recorded six birdies and a bogey.
'I started rolling the ball really well,' Wood said. 'My ball just kind of had eyes coming in. I had the wrong read on my 17th hole and the ball still went in. It's nice to have the opportunity to get some starts and relax and play well out here.'
Former American Ryder Cupper Chris Riley, Aaron Watkins, Richard Johnson, Esteban Toledo, Kenneth Staton and Steve Pleis are knotted in ninth place at minus-5.