His No.17 Roush Racing Ford crossed the finish line 0.622 seconds ahead of Jeff Gordon for his third win of the season and 13th of his Nextel Cup career.
"I was trying to save (the car) for the end and I had just enough," Kenseth said. "I'm so proud to be part of the team."
In the opening lap, series points leader Jimmie Johnson suffered a right-front flat and quickly fell to the back of the field down one lap to the leaders.
In the points race, Johnson has 3,365, Kenseth is second with 3,307 and Kevin Harvick is third with 3,048 points.
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