Ehlers skated onto a pass from Mark Jankowski on the rush and beat Jakub Dobes from the slot.
The best-of-7 series is tied 1-1. Game 3 is in Montreal on Monday (8 p.m.; CBC, TVAS, SN, TNT, truTV, HBO MAX).
Eric Robinson scored and Jalen Chatfield and Jankowski each had two assists for the Hurricanes, the No. 1 seed in the Metropolitan Division and in the Eastern Conference. Frederik Andersen made 10 saves.
Josh Anderson scored two goals for the Canadiens, the No. 3 seed in the Metropolitan Division. Dobes made 23 saves. Phillip Danault had two assists.
Carolina took a 1-0 lead at 2:33 of the first period. Robinson reached back into the slot with his stick and redirected William Carrier’s shot past Dobes’ left pad as the goaltender slid to his right.
Montreal tied it 1-1 at 11:11. Kaiden Guhle intercepted Taylor Hall’s clearing attempt and passed to Danault, who fed Anderson for a shot that deflected off the left skate of Hurricanes defenseman Alexander Nikishin.
Ehlers put the Hurricanes ahead 2-1 at 17:03 of the second period with an outstanding individual effort. He carried the puck from the red line, before turning to his backhand then his forehand. Ehlers then wrapped a shot around Lane Hutson and through the five-hole.
Anderson made it 2-2 at 12:51 of the third period when he scored on a net-front scramble.
