Martin, 50, the oldest driver in the Chase and the current points leader, won for the fifth time this season and the first time in his career at the New Hampshire Motor Speedway in Loudon.
He won after dropping a lap behind the field but then reclaiming the lead with 28 laps to go as the rest of the field required late pit stops.
"This is just incredible," he said. "I'm sure I am dreaming."
Denny Hamlin, last weekend's winner at Richmond, finished second by passing third-place Juan Pablo Montoya before the final caution flag.
"I could have pushed (Martin) out of the way, but I respect him a lot," said Montoya, the pole winner.
In the overall points race, Martin is first (5,230), while Hamlin and three-time winner Jimmie Johnson share second with 5,195.
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