Hamilton and Hughes each had a goal and an assist for the Devils (30-12-4), who are 6-0-1 in their past seven games.
"We were coming off a good road trip (4-0-1), and this was the first of four games in six days," New Jersey coach Lindy Ruff said. "I thought we played the game the right way. We didn't give up a lot of opportunities, gave ourselves a chance to win."
Vitek Vanecek made 25 saves to extend his winning streak to seven games, which is tied for the longest in the NHL this season. He is also the first Devils goalie to win seven straight starts since 2010-11 (Martin Brodeur, Johan Hedberg).
"It's seven wins, but I'm trying to not think about that coming into the game," Vanecek said. "I'm just playing that game and just focusing on the game."
Sidney Crosby scored, and Tristan Jarry made 23 saves for the Penguins (23-15-8), who are 2-0-2 in their past four games.
"We played well enough to win, and the too many men penalty was the right call," Pittsburgh coach Mike Sullivan said. "I thought we did a really good job defending. It boils down to details."