Victor Schwamkrug (69), Wes Short (65), Andre Stolz (65) and Tommy Tolles (67) shared second place at 9-under-par 135.
Chopra got going quickly at The Glen Club. He birdied the par-4 second from 18 feet out. He then notched back-to-back birdies from the par-3 fourth to get to minus-7. He later converted a 20-foot birdie putt on eight.
He dropped his second shot within seven feet of the cup to set up birdie at the 13th. Chopra then rolled off three straight birdies. He stuck a wedge inside eight feet at the 15th and knocked a wedge to three feet at the next.
Chopra capped his run of three straight birdies after hitting a 6-iron to six feet at the par-3 17th. He found big trouble at the last however. He knocked his second shot in the water and that led to a double-bogey.
'I couldn't help myself on the last hole,' said Chopra. 'It was downwind and I had 225 yards to carry the water. The wind just knocked it down. Then I got too cute on the next shot.'
The double-bogey at the last cost him a three-stroke advantage, but Chopra wasn't displeased.
'Maybe it will help having a one-shot lead,' he said. 'With a three-shot lead, you might think about protecting your lead.'
Schwamkrug, who is making just his second Nationwide Tour appearance of the season, had an up-and-down round. He started on the back nine and ran off three straight birdies from the 13th.
However, he dunked a shot in the water at 17 and that led to a double-bogey. He came right back to birdie the next to make the turn at 8-under.
He birdied the first and three-putted for bogey at the fourth, before sinking a four-foot eagle putt at the par-5 fifth. He later bogeyed the eighth for a round of 69.
Short birdied four of his first five holes before bogeying the seventh. He notched back-to-back birdies around the turn at No. 9 and 10. He closed a stellar round of 65 with birdies at the 16th and 18th.
Stolz started on the back nine with five straight pars. He birdied the 15th and 18th before catching fire on the front side. He notched back-to-back birdies from the second and again from the fifth. His final birdie of the round came at the par-4 eighth.
Tolles got going with a birdie at the fifth. He then made two in a row with birdies at Nos. 9 and 10. Tolles drained three straight birdies from the 15th, before a bogey at the last cost him a share of the lead.
Casey Martin is alone in sixth place at 8-under-par 136. David Branshaw, D.A. Points, Vaughn Taylor, Bo Van Pelt and Zach Johnson are one stroke further back at minus-7.
The cut line fell at 2-under-par 142 with 69 players surviving to play on the weekend.