A weather delay during the round led to a suspension of play with six players still on the course -- none with a chance to affect the leaderboard.
Both co-leaders had a runner-up finish last year -- Duke in New Orleans and Wi in Milwaukee.
Perry opened his round with three straight birdies and put himself in position to win for the third time this year. He is third on the FedEx Cup points list and fourth in the Ryder Cup standings.
In a bid to make the Ryder Cup team, which is now a virtual certainty, Perry chose to skip both the U.S. Open and next week's British Open.
"I've gotten hammered (with criticism) for doing that," Perry said.
Among those at 66 was Woody Austin, who is also making a bid for the Ryder Cup team.