Laird was third at the start of day two, but the Scot carded a five-under-par 67 to claim a one-stroke lead at the Silverado Country Club in Napa, California.
A three-time winner on the PGA tour, Laird holed six birdies and a bogey to close the day at 10 under overall.
South Korean Bae Sang-moon and American Zachary Blair are a shot further back.
Bae - co-leader overnight - dropped to second following his round of 69.
Blair, who started on the back nine, powered up the standings thanks to a blemish-free 66 that included six birdies.
American pair Scott Langley and Mark Hubbard are tied at eight under alongside Swede David Lingmerth.
Langley recovered a from a bogey at the third hole to sink seven birdies - three of those coming in succession starting at the 16th - as he shot a six-under 66.
Compatriot Hubbard went even better, producing a 65 that featured an eagle at the seventh hole.
Lingmerth had a second-round 68.
Japanese Hideki Matsuyama is in sole possession of seventh spot at seven under following his 67.
American quartet Brooks Koepka (70), Tom Gillis (68), Hunter Mahan (68) - a winner during the FedEx Cup play-offs - and Cameron Tringale (69) are tied at six under.
A group of 10 players are five shots off the pace heading into the third round, including Canadian Adam Hadwin (69) and American Matt Kuchar (68).
Joining the pair at five under are Americans Hudson Swafford (69), Cameron Wilson (68), Scott Brown (68), Bryce Molder (69), Byron Smith (66) and Colt Knost (71), as well as Australian duo Stuart Appleby (70) and Cameron Percy (70).
Further down the leaderboard, Andres Gonzales (74) dropped six strokes off the pace having enjoyed a share of the lead overnight.
Meanwhile, Australian cancer survivor Jarrod Lyle (70) made the cut.
Lyle, who has not played on Tour since 2012 as he battled cancer, finished two under after 36 holes.