Ondrej Palat, Brenden Dillon and Jesper Bratt also scored for the Devils (21-10-3), who have won three in a row. Jacob Markstrom made 19 saves and Jack Hughes has two assists.
"It was kind of a slow start for both teams; both teams were pretty structured and did a really good job in the neutral zone and both teams were breaking out quickly and efficiently," Devils coach Sheldon Keefe said. "It took a little bit to really get going. You win the first period, power play comes through to help us win the second period."
Jordan Kyrou scored in his fifth straight game, and Jordan Binnington made 24 saves for the Blues (15-15-3), who are 1-2-1 in their past four.
"I thought our first 15 minutes, I thought it was pretty good," Blues coach Jim Montgomery said. "I thought our intensity was there, I thought we were a little bit faster than they were. They scored that goal, and the air came out of the balloon.
"We made it easy to be checked. Jersey did a great job of checking. Their habits and details were superior to ours after they scored that first goal. And that's where we've got to become a little more resilient."
Palat made it 1-0 at 15:13 of the first period off a set play by defenseman Luke Hughes, who put a puck hard off the boards from his side of the red line into the stick of Palat for a one-timer to Binnington's short side that grazed his right shoulder.
"It's a broken play," Montgomery said. "They tried to hit the guy through the middle of the ice. I think it went through his legs or under his stick, off the end wall, they had speed on the outside. The guy made a good shot."