Matt Niskanen scored Washington's only goal in the second period on the power play.
"We were dangerous for some shifts, some periods of time and probably a little bit of each period," Niskanen said. "We were on the attack and had some looks, but we just couldn't get that second or third whack at one to just bury it."
The Capitals went 1-for-5 on the power play, including a 6-on-4 advantage for the final 42.9 seconds with Blue Jackets defenseman David Savard in the penalty box for hooking Jakub Vrana and Holtby on the bench for an extra attacker.
The Blues Jackets power play, which entered the game ranked last in the NHL (11.9 percent), went 2-for-3 and is 3-for-6 in the past two games.
"I think we're working harder," Duclair said. "I think we're working as a five-man unit. When we get out there, we don't have the mentality of just, 'It's the power play.' You want a mentality of, 'It's still 5-on-5.' We know the type of skill of talent we have on both units, and if we just put the work into it, I think they're going to start going in."
Duclair is tied with Josh Anderson for the Columbus lead with seven goals, including four on the power play.
"He has scored some big goals for us, has done some good things offensively," coach John Tortorella said. "He's going to have to learn how to check or he just won't get the ice time, but he has certainly scored some big goals. He's been really good for us on the power play."
Tortorella credited Bobrovsky with holding the Blue Jackets in the game in the first period, when they were outshot 15-9, until Oliver Bjorkstrand's power-play goal with 2:44 remaining gave them a 1-0 lead.