Former U.S. Amateur champion Bubba Dickerson fired a 67 of his own to finish alone in fourth place at 12-under-par 204. Chris Couch, who is already a two-time winner on the Nationwide Tour this season, was one shot further back at 11-under-par 205 along with Kevin Gessino-Kraft.
Olsen was part of a five-way tie for first to start the day at the Pete Dye Golf Club and played his second shot inside 6 feet for a birdie at the par-4 first. Olsen added back-to-back birdies from the fifth, but he found trouble with a bogey at the seventh.
The 38-year-old countered with a birdie at the par-5 eighth, but he struggled to another bogey at the ninth to make the turn at 11 under. Olsen came back at the par-4 10th and hit his approach to 7 feet for another birdie.
Olsen moved to 13 under with a birdie at the 12th, but dropped a shot with a bogey at the 13th. At the par-4 14th, Olsen hit his second shot to 6 feet and converted the birdie putt to get back to minus-13.
Olsen hit his third shot out of the rough to 7 feet at the par-5 15th and rolled in the birdie try. He kept on cruising with another birdie at the par-4 17th to move two shots clear of his closest competitors. Olsen gave that shot back with a bogey at the last, however, but remains the front-runner heading into Sunday.
'I felt pretty good,' said Olsen. 'This is nice to be in the lead and I wish I was leading by more. There's a lot of golf tomorrow, I'd rather be in the lead for sure.'
Gore became a fan favorite with his performance in the U.S. Open and he has continued to play well on the Nationwide Tour. Gore birdied two of his first four holes, but faltered to a bogey at the sixth.
The 31-year-old birdied the 11th and hit his second shot within 6 feet of the hole for a birdie at the par-4 12th. Gore added a birdie at the 15th to finish within one of Olsen.
'You just gotta take it for what it is and see what happens,' said Gore, who shot a 68.
Felton collected three birdies on the front nine and added a birdie at the par-4 12th to move to 10 under. He then caught fire with three straight birdies starting at the par-5 15th to join Gore in second place after a round of 65.
Nationwide Tour money leader Troy Matteson carded a 2-under 70 to share seventh place with Aaron Barber, Bubba Watson and Doug LaBelle II at 10-under-par 206. Tom Scherrer and Jim McGovern followed at 9-under-par 207.