The game-winning goal began when Carolina had an extra attacker on the ice thanks to a delayed penalty call against Washington.
However, before the Capitals touched the puck and killed the play, Rask beat goalie Braden Holtby from the short side and snapped a 1-1 tie.
Aho added his empty-net goal with 1:29 remaining.
The victory ended a three-game Hurricanes' losing streak.
This was the second time in nine days the two teams have met. Washington scored a 5-4 overtime victory vs. the Hurricanes on Jan. 2, and these teams will play again at Carolina Friday night at 7:30.
This loss stopped a five-game Washington winning streak. Also, the Capitals had won 10 straight at home, the longest win streak of that type in the NHL this season.
Washington had not lost at home since the Los Angeles Kings handed the Capitals a 5-2 defeat on Nov. 30. The Capitals couldn't create much on offense against the Hurricanes, who don't allow many shots per game.
Carolina finished with a 33-28 edge in shots.
Jordan Staal gave Carolina a 1-0 lead with a shorthanded breakaway goal.
He picked off a soft pass from Capitals defenseman John Carlson from near the left boards and turned it into a breakaway, beating Holtby with 8:27 remaining in the second period for an unassisted goal.
Lars Eller tied it for Washington later in that period, one-timing a perfect pass from T.J. Oshie past goalie Scott Darling with 3:55 left.
Darling finished with 27 saves in the victory.
In off-the-ice news, the NHL announced on Thursday that Dallas businessman Tom Dundon will take over as Carolina majority owner. He closed the deal with Peter Karmanos Jr., who will keep a minority ownership interest with the Hurricanes. A press conference to announce the move is scheduled for Friday.
--Field Level Media
Carolina | Washington | |
Sebastian Aho 1 | Points | Lars Eller 1 |
Sebastian Aho 1 | Goals | Lars Eller 1 |
Elias Lindholm 1 | Assists | Christian Djoos 1 |
N/A | Power Play Goals | N/A |
Jordan Staal 1 | Short Handed Goals | N/A |
Scott Darling .964 | Save Percentage | Braden Holtby .938 |
Scott Darling 27 | Saves | Braden Holtby 30 |
Team | Shots | Goals | Power Play | Penalty Kill | Penalty Mins | Face Offs Won |
Carolina | 33 | 3 | 0-1 | 3-3 | 6 | 28 |
Washington | 28 | 1 | 0-3 | 1-1 | 2 | 27 |