Sidney Crosby tied things late in regulation and Kennedy won it with his fifth goal of the season, a wrist shot from the left circle.
Marc-Andre Fleury stopped 27 shots for Pittsburgh, which remained unbeaten in March.
Claude Giroux scored his 10th goal of the season late in the second period for Philadelphia, but the Flyers couldn't make it hold up on a night they played without forward Danny Briere and defenseman Nicklas Grossman.
Ilya Bryzgalov made 33 saves but let two slip by late.
CAPITALS 3, RANGERS 2, SO
Braden Holtby made 30 saves in regulation and overtime and stopped three of four Rangers in the shootout for the Capitals.
Ovechkin scored in the second round of the shootout, only to see Derek Stepan tally for New York to knot it at 1-1 after three rounds.
After Holtby denied Brad Richards, Backstrom beat Lundqvist to decide the contest in the fourth round.
RED WINGS 2, DUCKS 1
The Ducks, who trail idle Chicago by three points for the NHL's best record, have dropped consecutive games in regulation for the first time this season following a 22-3-4 start that was the best in franchise history. They also had back-to-back shootout losses on the road against the Phoenix Coyotes earlier this month.
Anaheim captain Ryan Getzlaf scored on a power play with 46 seconds left in the second period, ending his 13-game goal drought against Detroit. Jonas Hiller stopped 21 shots after going 8-0-2 with a 1.86 goals-against average and .933 save percentage in his previous 10 starts.
CANUCKS 3, AVALANCHE 2
DENVER -- Mason Raymond and Alexandre Burrows scored in the second period and Vancouver moved into sole possession of first place in the Northwest Division with its fourth straight win.
Jason Garrison added a goal for the Canucks, who moved ahead of idle Minnesota by two points for the conference lead.
Cory Schneider made 26 saves in his fourth consecutive start. He is 5-0-1 with two shutouts against the Avalanche.
Jamie McGinn and PA Parenteau scored for free-falling Colorado, which has dropped six of seven.
Jean-Sebastian Giguere made his first start since March 5 in Detroit and allowed three goals on 30 shots. Giguere is 9-11-4 against Vancouver.
ISLANDERS 3, PANTHERS 0
It was Nabokov's third shutout this season for the Islanders.
MacDonald scored his second goal of the season at 6:05 of the first period on the power play.
FLAMES 3, BLUES 2
CALGARY, Alberta -- Jarome Iginla scored the winning goal at 12:58 of the third period and Calgary snapped a three game skid while extending its winning streak on home ice to seven straight games.
Iginla found himself on a partial breakaway thanks to a nice pass from Alex Tanguay. St. Louis defenseman Wade Redden knocked the puck away, but Iginla stayed with the puck to score a wrap-around goal.
T.J. Oshie had a goal and an assist for the Blues, who had won four of their past five.
JETS 3, LIGHTNING 2
WINNIPEG, Manitoba -- Bryan Little had a goal and two assists and Winnipeg made Tampa Bay's bad day worse.
The Lightning fired coach Guy Boucher earlier in the day and assistants Martin Raymond and Dan Lacroix shared coaching duties against the Jets.
Winnipeg goalie Ondrej Pavelec made 23 saves, while Cedric Desjardins stopped 21 shots for the Lightning.
Copyright 2013 by The Associated Press
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