It was the fifth home win in 13 tries for the Oilers this season, equaling Nashville and Phoenix for the fewest number of home victories in the Western Conference.
Taylor Hall and Tom Gilbert both scored power-play goals in the second period to give Edmonton a 3-2 lead but Steven Stamkos tied it with the lone goal of the third period. It was the 22nd goal of the season for Stamkos, who is second in the NHL in that category behind Pittsburgh's Sidney Crosby and his 26.
After Stamkos missed in the shootout's second round, Omark scored to end the game.
Nikolai Khabibulin was perfect in the shootout after making 38 saves in regulation and overtime. Dan Ellis stopped 20 shots before allowing the two shootout goals.