With speed throughout the lineup and a power play that is clicking on a nightly basis, it is no wonder why the Rangers are on quite a roll.
''Starts are important,'' Lundqvist said. ''If you can jump out and start the right way and then get the momentum, then I think you set the tone for the rest of the game and you gain confidence right away.''
The Rangers' offense broke out for the second straight day, after winning 1-0 over Detroit on Thursday. They recorded four goals for the third time in five games.
Lundqvist, who got the day off when New York won 4-1 at Ottawa on Saturday, was sharp in making 24 saves. He has allowed fewer than three goals in six consecutive starts. New York, 11-3-1 in its last 15 games, improved to 12-11-3 at home.
''It was a tough back-to-back for us,'' Nash said of the Rangers' weekend sweep. ''Traveling (Saturday) and coming home to a team that is right on our heels ... it's a huge four points.''
Washington dropped its fifth straight (0-3-2) and completed a winless three-game trip against Metropolitan Division foes. The second-place Rangers lead the fifth-place Capitals, who have played two fewer games, by five points.
''We're in a slump right now, that's for sure,'' Capitals forward Nicklas Backstrom said. ''It's tough, but we've got to find a way to get through it. We've got to start playing way better than we're doing right now.''
Nash scored 1:10 in and added a power-play tally later in the first, giving him seven goals in eight games. Derek Stepan also scored in the first to chase goalie Philipp Grubauer. Ryan Callahan added a short-handed goal in the second.
Alex Ovechkin netted the only goal for Washington, which committed four penalties in the second to thwart hopes of a comeback.
''All the experienced guys, we've got to really stick together here and battle through,'' Backstrom said. ''It's tough, but I think we're going to turn this around, and we're going to do it next game. We're going to be much stronger after that.''
Despite recording only nine shots in the first, New York carried a 3-0 lead into the intermission.
Nash got the offense churning when he intercepted a clearing attempt by defenseman Dmitry Orlov at the left point and steamed into the Washington zone. He cruised through the left circle, came in alone on Grubauer, shifted to his backhand and lifted in a shot.
Nash made the most of that and squeezed a shot from the right circle through Grubauer for his team-leading 14th goal at 16:06.
Stepan pushed the lead to three just 2 seconds after Alzner's penalty expired. After breaking a 13-game goal drought Saturday, Stepan netted his second in two days when he snapped in a wrist shot from above the circles.
That ended Grubauer's short night as he was replaced by Braden Holtby. Grubauer was pulled in the first period for the second straight game. He yielded three goals on 14 shots Friday in a loss to Columbus.
''It's not the way I wanted it to go,'' Grubauer said. ''It's my job to stop the puck, and I didn't stop it today.''
Washington produced a brief spark when slashing calls against Chris Kreider, in the final minute of the first, and Carl Hagelin in the opening minute of the second, gave the Capitals a two-man advantage and generated a goal.
Ovechkin took a pass from Mike Green in the left circle and one-timed a hard shot that beat Lundqvist at 59 seconds for his NHL-leading 35th goal and fourth in six games. Washington put more pressure on during the second half of the power play, but the Rangers netted the next goal.
Dominic Moore and Callahan raced out on a short-handed 2-on-1 rush, and Moore fired a shot that Holtby deflected back into the slot. The hard-charging Callahan beat Orlov to the puck and slammed a shot in before barreling into the net.
''You're not going out on the PK and thinking, `I want to score a goal by any means,''' Callahan said. ''I feel like with the guys we have killing, and the speed we have on our killers, if the opportunity presents itself, we are going to go for it.''
Green had a goal waved off by a Capitals penalty in the second.
NOTES: Rangers D Ryan McDonagh had two assists. ... The Capitals had failed on 14 straight power plays over six games before Ovechkin's goal. ... Erat was called for three penalties, including one for slashing when he jammed his stick between the legs of a seated Brian Boyle.