Gustafsson has six goals and five assists during a Capitals season-best seven-game point streak. Evgeny Kuznetsov, who set up the goals by Gustafsson and Strome, has points in five in a row.
Dowd's goal poking the puck through Jake Allen's pads came minutes after son Louie was shown on video screens to celebrate his third birthday.
Wisconsin native and former University of Wisconsin star Cole Caufield scored his 20th and 21st goals of the season for the Canadiens in their fifth consecutive loss. He's the first Montreal player to reach 20 goals in 37 of fewer games since Martin Rucinsky and Brian Savage in 1995-96.
Allen allowed nine goals on 38 shots for the Canadiens, who have lost eight of nine.
NOTES: Forward Nicolas Aube-Kubel was a healthy scratch for the Capitals. Joe Snively replaced him in the lineup, playing his sixth game of the season and first since Nov. 15. ... Defenseman Chris Wideman returned for Montreal to take the spot of injured rookie Kaiden Guhle.
Canadiens: Visit the Nashville Predators on Tuesday night.
Capitals: Wrap up their three-game homestand Tuesday night against the Buffalo Sabres.
Follow AP Hockey Writer Stephen Whyno on Twitter at https://twitter.com/SWhyno
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