Jason Dufner has a two-stroke cushion over Canada's Graham Delaet, who is in sole second place after a 66, going into the final round of the Zurich Classic of New Orleans.
John Rollins lies a shot further back in third after a 69, tied with South Africa's Ernie Els, who carded a 68.
Dufner's been in winning positions before, even at last year's USPGA Championship where he lost in a play-off to Keegan Bradley, and has had trouble sealing the deal in the past.
"For me, it means instead of two good rounds I've had three good rounds, so maybe we can make it four, starting tomorrow," Dufner said.
"I don't really think about all that type of stuff. Obviously, I know that I hadn't played as well as I would like on the weekends, try to identify some of the reasons why and try to implement some of those tomorrow."
He went on: "Right now a win would be great.
"Obviously, I've been be knocking on the door with a lot of solid rounds, lot of solid play last year at the end of the year, but I take pride in being consistent with my game. I don't shoot too many high numbers. I don't feel like I'm very far away from playing well each week."