Donald had five birdies and one bogey Friday, and goes into the third round at 7-under 133 through 36 holes.
"I'm really not putting myself into too much trouble and I'm very consistent off the tee," Donald said. "I'm hitting a decent amount of greens ... and just kind of everything is working very well."
First-round leader Sean O'Hair (69), defending champion Brett Wetterich (68) and Fredrik Jacobson (67) are tied for second at 6-under 134.
Two-time Masters champion Phil Mickelson (70) is one of 15 players tied for 30th place at 1-under 139.
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