One of the local favorites, Casey Martin partnered with Stanford teammate Notah Begay III to take second place at 10-under-par 62.
Youngsters Charles Howell III and Honda Classic champion Matt Kuchar shot a nine-under 63 and share third place with three other teams. Stewart Cink and PGA Champion David Toms, Senior Tour members Bob Gilder and Tom Wargo and Jack Nicklaus and son Gary all shot 63s to trail the leaders by three shots.
This two-day tournament is played at The Reserve Vineyards & Golf Club, which takes 17 holes from the Fought Course and one hole from the Cupp Course, the par-5 16th.
McCarron and Henninger combined for five birdies on the front side but the duo did most of their damage on the second nine at The Reserve Vineyards & Golf Club.
The pair opened the back nine with three birdies in their first four holes. They birdied the par-5 15th and took advantage of the par-5 16th, the lone hole from the Cupp course. McCarron holed an eagle putt and then scored a birdie at the last for their round of 60.
David Duval, who was scheduled to play in this event with his father Bob until the elder Duval had knee surgery a few weeks back, teamed with Dudley Hart and finished seventh at minus-8.
Tom Lehman and Chris DiMarco teamed up for a seven-under 65 and share eighth with Craig Stadler and Steve Elkington.
Defending champions Billy Andrade and Brad Faxon carded an opening-round 66 and are tied for 10th with the tandem of John Cook and Fred Couples.
Tournament host Peter Jacobsen and his partner Arnold Palmer are in last place with a score of five-under-par 67.