Chris Simon scored late in the second period to complete Washington’s rally from a two-goal deficit in beating New York.
The Capitals, with 86 points, hold a four-point lead over the Florida Panthers atop the Southeast Division.
Washington improved to 15-1-3 in its last 19 home games. The Capitals are 24-6-5 since Jan. 1.
Simon broke a 3-3 tie when he beat Kevin Weekes from the left circle for a power-play goal with 2:45 left in the second period.
The Capitals controlled play against an inept Islanders penalty-killing unit and scored two man-advantage goals in three chances, sparking their comeback from a 3-1 first-period deficit.
Washington rebounded after a shaky opening period that saw New York hold a 17-7 edge in shots. The Capitals, however, outshot the Islanders 31-9 after that, dominating the second and third.
