Jon Mills fired a 9-under 63 and is alone in second place at minus-16. Craig Bowden shot a 6-under 66 and is knotted in third place with Nick Cassini, who managed an even-par 72. The pair is tied at 13-under-par 203.
Wind gusts reached up to 35 miles per hour on Saturday, but McKenzie handled the conditions as well as anyone. He hit 16 out of 18 greens in regulation, but hit only 50 percent of the fairways.
'It was windy,' said McKenzie, whose best finishes this season were a pair of third-place ties in the last two months. 'The objective is to get it on the green somewhere and give yourself a putt at it.'
McKenzie birdied three holes in a row from the second, then birdied the par-3 sixth. He dropped a shot at the eighth, but still made the turn at 3-under 33.
McKenzie birdied two of his first three holes on the back nine to reach 18 under par for the first time in the tournament. He bogeyed the 14th, but rebounded with a birdie on the par-5 17th.
'I played alright,' said McKenzie, who has not missed a 36-hole cut since the beginning of August. 'I struck it well for most of the day. But overall it was very uneventful.'
McKenzie narrowly missed out on automatic PGA Tour spot last year when he finished 23rd on the Nationwide Tour money list, three places shy of a berth.
This year he is 25th on the money list and with a big finish on Sunday, McKenzie can move up and secure his PGA Tour card for the 2006 season.
Jeff Gove (68), Cameron Percy (69), Jeff Klauk (69) and Fran Quinn (70) are tied for fifth place at 12-under-par 204.
Bubba Dickerson shot a 3-under 69 and is knotted in ninth place with Jerry Smith, who only managed a 1-over 73 on Saturday. The pair is tied at minus-11.
Overnight leader Doug LaBelle II struggled to a 4-over 76 in the third round and fell into a group tied for 11th place at 10-under-par 206.