Tidland (62), Coles (66) and Enloe (65) completed 36 holes at 11-under 128 and are three clear at Hardscrabble Country Club.
Kris Blanks and Brenden Pappas each carded rounds of 5-under 65 and are knotted in fourth place at 8-under 132.
Tidland started on the 10th tee and promptly birdied his first two holes. He birdied 13 and 15 to get to 7 under for the championship, but his final first-nine birdie came from 20 feet at the 16th. That got Tidland to the turn on Friday at minus-8.
He missed the green with an 8-iron at the par-3 second and made bogey. Tidland played holes 5-7 in 4 under par, thanks in part to a 25-foot eagle putt at the sixth.
Tidland parred his last two to earn his share of the lead.
'I had a lot of good opportunities today,' said Tidland, who owns one Nationwide Tour victory. 'I made a lot of them. I drove it nice and hit lots of good wedges and short irons.'
Coles, a four-time champion on the Nationwide Tour, also played the back nine first on Friday. He birdied No. 14, but lost the stroke thanks to a bogey at the closing hole.
Coles birdied the second and third to get to minus-9. At the par-5 sixth, Coles hit a 4-iron to 8 feet and converted the eagle putt.
He birdied the par-3 eighth and found himself at 12 under par. Unfortunately for Coles, he bogeyed the par-4 ninth to fall into a share for first.
'It's playing really nice today,' stated Coles, an Englishman. 'You get rewarded for a good shot and you've got to work hard when you don't hit one that's not so good.'
Enloe, like his fellow co-leaders, teed off on No. 10 to start his second round. Unlike those who joined him at minus-11, Enloe made it around Hardscrabble Country Club without a bogey.
Overnight leader Phil Tataurangi struggled to a 1-over 71 and fell into a tie for sixth place with Dustin Risdon, who posted a 68 Friday. They finished at minus-7.
The 36-hole cut fell at even-par 140 and Kevin Johnson, a playoff winner in two of the last three Nationwide Tour events, missed the weekend by a single stroke.