Oshie scored twice in a 91-second span in the second period to push the lead to 3-0. After his second tally, the standing-room only crowd of 19,839 broke into chants of, "USA, USA," in honor of Oshie’s selection to the United States Olympic team Wednesday.
It was the first two-goal game of the season for Oshie.
Elliott, who improved to 11-1-2, picked up his third shutout of the season and 24th of his career. He stopped 13 shots in the opening period, including a pad save on Jarret Stoll.
Brenden Morrow, Vladimir Tarasenko and Barret Jackman also scored for St. Louis.
Morrow scored just 4:42 into the game to give the Blues to a 1-0 lead. Kevin Shattenkirk, another Olympic team selection, missed on a long shot, but Morrow pounced on the rebound at the side of the net and banked it in off goalie Martin Jones.
Oshie scored on the power play at 11:41 of the second off the rebound of a shot by Jaden Schwartz. Less than two minutes later, Oshie whipped a shot behind replacement Ben Scrivens.
Jones, who fell to 8-3, gave up two goals on 14 shots and was pulled after Oshie’s first tally.
The Kings had won 15 of the previous 18 games between the teams including postseason play.
Los Angeles won four successive games after falling behind 2-0 in the opening round of the Western Conference playoffs last season and also swept the Blues in four games in the 2012 conference semifinals.
Notes: St. Louis RW Ryan Reaves returned to the lineup after missing 17 games with a broken hand. … The Kings have outscored their opponents by 15 goals in the first period this season. … St. Louis G Jaroslav Halak missed the game due to the flu. He is listed day to day. Jake Allen was recalled from the Chicago Wolves of the AHL to serve as backup. … St. Louis coach Ken Hitchcock recorded his 100th regular-season win with the Blues. … Jones lost his third in a row after a franchise-record 8-0 start to his career. … St. Louis RW David Backes, the third St. Louis player chosen to the Olympic team, missed his third successive game with an upper-body injury.