The opening round was suspended due to darkness with seven players still on the course at El Cid Golf & Country Club. The start of the round was delayed by an hour and 15 minutes due to heavy fog.
Craig Taylor is two shots back at 6-under-par 66. Scott Gibson, Brien Davis and Jamie Gomez are knotted in third place after the trio opened with rounds of 5-under 67.
Harris was 4-under par at the turn and collected another birdie before playing the par-5 seventh, his 16th hole of the round. He landed in a bunker with his second, but holed out for an eagle.
Harris added another birdie at No. 8 to get two clear, a position he is not very familiar with on the Canadian Tour.
'I've never started like this,' said Harris, a University of Michigan graduate. 'I try not to think too much about it; it's each hole at a time, one shot a time.'
Harris is a four-time runner-up on the Canadian Tour and the 27-year-old thinks he can capitalize on his lead. Harris tees off early Friday morning and will likely avoid the winds that bothered players late on Thursday afternoon.
'It will be less windy with less heat on Friday,' said Harris, who played the 2004 season on the Nationwide Tour. 'That will be easier on the body and the mind.'
Chris Wall and Ryan Miller are tied for sixth place at 4-under-par 68.
Marcus Jones, George Bradford, Danny Paniccia, Glenn Collins, Jeff McCammon, David Mathis, Manuel Inman and Michael Walton are in the clubhouse tied for 10th at 3-under-par 69. Nik Tayler is 3-under par and has yet to complete his opening round.