A visit to Washington, however, could put both runs in serious jeopardy.
The NHL-leading Bruins will look to win an eighth straight road game and continue pulling away from the Capitals on Saturday while avenging their only defeat away from home since Thanksgiving.
Boston's rise to the top of the standings has been complicated lately by injuries, as coach Claude Julien's club continues to play without a number of its top forwards. While young standouts Milan Lucic and Patrice Bergeron are working their way back, Marco Sturm is out for the season and team goals leader Phil Kessel is expected to miss at least a few more weeks.
Defensemen Andrew Ference and Aaron Ward also remain out, but the Bruins (33-7-4) still scrambled for their fourth straight victory on Thursday, beating the New York Islanders 2-1 on the road despite getting outshot 41-27.
Tim Thomas' 40 saves sparked Boston, with the All-Star earning his third straight win. He has allowed just three total goals over that span, lowering his goals-against average to 2.00 - second-best in the league.
"Timmy was our best player," Julien said. "He held the fort."
Boston's standout line of David Krejci, Michael Ryder and Blake Wheeler was held off the scoresheet against the Islanders after combining for six goals and 10 assists in the previous three games, but the Bruins still improved to 28-4-1 since Nov. 1.
Martin St. Pierre, who has spent most of this season with Providence of the AHL, scored the game-winner for Boston, which took over the NHL points lead with the win.
"There are about six reasons why this team is different from previous Bruin teams," Thomas said. "One of the biggest things is that we're all on the same pages as the coaches are."
The Bruins had won five straight games overall when they visited Washington on Dec. 10, but the Capitals won 3-1 behind 33 saves from Brent Johnson. Boston hasn't lost on the road since, outscoring opponents 28-12 during its seven-game road winning streak.
The team hasn't won eight straight away from home since the final eight road games of the 1992-93 season.
It will have a tough task beating the Capitals, who are 18-3-1 at the Verizon Center. Washington (28-14-3) is also the Bruins' closest pursuer in the Eastern Conference, 11 points back.
"Obviously their home record is excellent," Julien said. "... We have to definitely be at our best if we want to make this a really good game."
The Capitals will be trying to rebound after dropping their last two home games, but they ended their three-game overall losing streak with Wednesday's 6-3 win at Pittsburgh.
Star winger Alexander Ovechkin, who had been held to one assist in his previous four games, snapped out of his swoon with two goals and an assist, all in the third period.
"When he gets in a slump and then breaks the slump, he doesn't break it just to break it," Capitals coach Bruce Boudreau said. "He gets two or three... That's what Alex does. He's a real emotional guy and he plays on that passion. And when he gets going, he's pretty hard to stop."
Ovechkin, who ranks second in the NHL with 29 goals, had a goal and an assist against the Bruins last month. Nicklas Backstrom, who had three assists Wednesday, also had a goal and an assist versus Boston.
This game will feature the top two offenses in the in the East, with both teams averaging more than 3.2 goals. Ovechkin, Backstrom, Krejci and Boston's Marc Savard comprise four of the NHL's top 15 point-scorers.