Dupuis' tally late in the second period handed Pittsburgh a 3-1 advantage and the Penguins went on to record the victory, giving them their third straight 100-point season.
Evgeni Malkin, Sidney Crosby, Jordan Staal and Chris Kunitz also contributed a goal and an assist each for Pittsburgh, which pulled to within a single point of the New York Rangers atop the Eastern Conference with seven games remaining.
Marc-Andre Fleury earned his career-best 41st victory with 32 saves.
Martin Brodeur made 23 saves for the Devils.
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