Keselowski took advantage of late pit stops by Joe Gibbs Racing drivers Kyle Busch and Denny Hamlin to surge into the lead and conserved enough fuel late in the race to post a 1-second verdict over Jeff Gordon.
The Penske Racing driver won his fifth race of the season and entered the winner's circle for the second time in the first three Chase for the Sprint Cup championship events.
He used the result to establish a five-point Chase points lead over Jimmie Johnson, who finished fourth at Dover.
Mark Martin logged a third-place finish while Carl Edwards rounded out the Top 5.
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