Ovechkin got a break on his first goal to make it 3-1 with 26 seconds left in the second period when Canucks forward Brandon Sutter cleared a rebound off his leg at the side of the net. He scored his second of the night in more familiar fashion, with a one-timer from the left face-off circle on the power play to make it 4-2 at 5:35 of the third.
Video: WSH@VAN: Ovechkin scores, Backstrom gets 600th assist
It was Ovechkin's 233rd power-play goal for Washington, moving him past Dino Ciccarelli for ninth in NHL history.
[WATCH: All Capitals vs. Canucks highlights]
But most of the talk afterward was about Ovechkin passing on a chance at a hat trick with the Canucks net empty, instead setting up T.J. Oshie to make it 5-2 with 1:41 left.
"Yeah, I was (surprised)," said Capitals center Nicklas Backstrom, who had three assists, giving him 601 in the NHL. "But you know what, I think he's so mature now, so he knows his hat trick is coming in the next couple of games. No biggie for him."
Oshie said something to Ovechkin right after scoring.
"Why did you pass me the puck?" Ovechkin said when asked what Oshie said. "But he was so wide open, and I tried to give him the pass. Save mine for next time."
Coach Todd Reirden, who was on Barry Trotz's staff when Washington won the Stanley Cup last season, said it was just one more example of Ovechkin's evolution.
"To me, that's huge," Reirden said. "His leadership, we all were able to see it last [season] when we won the ultimate prize in our sport, and yes, he scored some big goals, but a lot of it had to do with his leadership in our room and shot-blocking and commitment to overall game. He could have easily scored himself, but it wasn't even a thought. It doesn't bother him one bit. His leadership has gone to a new level."
John Carlson had a goal and two assists, and Braden Holtby made 22 saves for the Capitals (4-2-2). Washington allowed 18 goals its previous four games (1-2-1) but tightened up to open a three-game Western Canada road trip.
Video: WSH@VAN: Carlson tips home Vrana's feed on the rush
"(Defending) definitely was an area of focus, something we wanted to get better at," Reirden said. "We wanted our first road win to start our trip off right."
Anders Nilsson made 28 saves for the Canucks (5-4-0), who lost for the second time in six games.
"They're big, they're strong, they're skilled, they win puck battles, they manage the puck, they do everything that Stanley Cup-winning teams do," coach Travis Green said.
Carlson put Washington ahead 1-0 2:20 into the game, driving the net off the rush to redirect a Jakub Vrana pass over Nilsson's glove.
Troy Stecher tied it 1-1 at 7:30 of the second period with a point shot that Capitals forward Nic Dowd redirected over Holtby.
Evgeny Kuznetsov made it 2-1 at 9:29 of the second period with a one-timer from the top of the right circle on the power play, almost the mirror opposite of Ovechkin's power-play goal in the third.
Video: WSH@VAN: Kuznetsov blasts a one-timer past Nilsson
"Goalies don't respect him and [Backstrom] as much as shooters because they like to dump it off," said Carlson, who got the primary assist on each power-play goal. "It's big for us to catch goalies leaning back looking for where the puck is going to go next and surprise them a little."
Sven Baertschi scored 20 seconds into the third period to make it 3-2, converting a rebound on a power-play rush after Holtby made a blocker save on Brock Boeser's wrist shot.
Video: WSH@VAN: Baertschi cashes in on the rebound for PPG
But Ovechkin restored Washington's two-goal lead with his Capitals-high eighth goal.
"We made a game of it," Sutter said. "Unfortunately, they kept pulling away."
They said it
"We're a little more balanced, and when the time is right, I can slot some guys up for certain shifts." -- Capitals coach Todd Reirden on putting Alex Ovechkin, Nicklas Backstrom and T.J. Oshie on a line for a shift late in the second period, leading to Ovechkin's first goal of the night
Video: WSH@VAN: Ovechkin scores on fortunate redirect
"We let them take the game to us. It's a good hockey club over there. There's a reason why they won the Stanley Cup." -- Canucks center Bo Horvat
Need to know
Backstrom got his 600th NHL assist in the same city where the Capitals picked him in the first round (No. 4) of the 2006 NHL Draft. "It's pretty funny how it works," he said. … Washington went 2-for-4 against Vancouver and leads the NHL on the power play (38.7 percent). … Green said there is a "good chance" center Elias Pettersson (concussion) will travel for a two-game road trip Wednesday and Thursday after he skated with the Canucks on Monday. The rookie has missed four games.
Capitals: At the Edmonton Oilers on Thursday (9 p.m. ET; SN1, SNE, SNO, NBCSWA, NHL.TV)
Canucks: At the Vegas Golden Knights on Wednesday (10 p.m. ET; SN360, ATTSN-RM, NHL.TV)
Video: Ovechkin powers Caps past Canucks with four points