"It felt a little odd, I guess," Langenbrunner said. "It had been a while since we scored in the first period. We finally did the things we needed to score goals: we were going to the net hard, especially in that first period. We were battling well and, if we keep doing that, it will continue to happen."
Brian Gionta also scored for the Atlantic Division-leading Devils and Martin Brodeur was the beneficiary of the early support, making 31 saves as New Jersey won for the fourth time in the last five games.
"Having a lead is what you play hockey for," Brodeur said. "You always want to be ahead but sometimes you can't control these things. It was definitely nice to come out and get two goals early in the game."
The Devils posted their ninth win in the last 10 at home and cooled off one of the NHL's hottest road teams.
The Panthers, who had won seven of the last eight on the road coming in, got goals from David Booth and Jay Bouwmeester.
The tallies by Langenbrunner and Clarke staked the Devils to a 2-0 lead.
Dainius Zubrus set up the first score by circling behind the Panthers net before feeding a backhand pass to Langenbrunner for the tap-in past Tomas Vokoun at 9:08.
Clarke followed with his first goal as a Devil at 13:35. New Jersey controlled play throughout the period with a 12-6 shot advantage.
The Panthers were far more aggressive in the second, outshooting the Devils 14-5 and getting a goal from Booth at 7:30. Booth took a pass from Stephen Weiss and calmly skated across the slot, waiting for the opening to slip the puck by Brodeur.
The Devils almost countered that goal in the closing seconds of the period when Zach Parise flipped a shot off the crossbar.
In the third, Parise set up Gionta's power-play goal that put New Jersey up 3-1. With the Devils on a 5-on-3 advantage, Parise in the right circle fed the puck to Gionta at the goal line for a redirection inside the left post.
The two-goal cushion soon vanished as Panthers defenseman Bouwmeester joined the attack and rifled a close-in shot over Brodeur's left shoulder at 5:06 to trim the Devils lead to 3-2.
Brodeur preserved the win with a sprawling save against Weiss in the closing seconds.
Florida general manager and coach Jacques Martin felt the Panthers didn't get contributions from enough players.
"Some of the guys worked hard and some of the guys didn't work hard," Martin said. "Against the Devils, you have to be patient and make the right decisions. I thought we had an outstanding performance from Stephen Weiss, David Booth and Nathan Horton. They had most of our chances."
That line combined for nine of the Panthers 33 shots.