After getting around Clint Bowyer and Brad Keselowski, Stewart took the lead with 30 laps to go and then held off a determined Jimmie Johnson through a pair of restarts to win at Las Vegas for the first time in 14 tries.
Johnson drove his backup car to second place. He had wrecked his primary car Saturday during a practice run.
Dale Earnhardt Jr. started fast with the lead in 70 of the first 71 laps but finished 10th after a series of problems with his car.
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