The Jets have 56 points, five more than the Kings and the Canucks.
Winnipeg chased Vancouver goalie Richard Brodeur by building a 7-1 lead on MacLean's second goal of the night with 10:26 remaining in the second period.
Vancouver's Tony Tanti scored his 38th goal of the season.
Quebec 1, Minnesota 0--Goaltender Mario Gosselin, repeating a shutout performance of a year ago, stopped 34 shots by the North Stars, and Peter Stastny scored on a first-period power play as the Nordiques at Minneapolis.
Stastny's goal was his 38th of the season.
The North Stars had not been shut out since their 8-0 loss to Gosselin and the Nordiques on March 13, 1985.
Quebec padded its Adams Division lead to nine points over the second-place Montreal Canadiens. Third-place Minnesota remained three points behind the first-place Chicago Blackhawks in the Norris Division.