Anderson stops 38 shots, Butler scores 2 for Sens
Butler made a nice toe-drag move against defenseman Mark Giordano, then snapped a shot over goalie Miikka Kiprusoff's glove to break a 1-1 tie in the third period.
The 24-year-old forward added his second of the night at 16:12 to make it 3-1 after bursting down the right wing and firing a wrist shot inside the far goal post.
Daniel Alfredsson also scored for Ottawa (9-9-1).
Anderson was impressive after giving up four goals on six shots and getting pulled against Buffalo on Friday. He has bounced back with two solid outings, also stopping 31 of 33 shots in Ottawa's win Saturday at Toronto.
Two of his best stops Tuesday came in the second minute of the game when he denied Lee Stempniak on close-in chances after he was set up in front by Paul Byron.
On the heels of a five-game losing streak, the Senators have won two straight. They are halfway through a six-game trip that continues Thursday against Edmonton.
Tom Kostopoulos scored the lone goal for the Flames (7-9-1), who had won eight of nine against Ottawa, dating to 2004. Miikka Kiprusoff had 29 saves. Calgary has won just two of its last seven at home.
Ottawa took a 1-0 lead with 1:16 left in the second period.
When Jarome Iginla couldn't get the puck past Nick Foligno along the side boards, Foligno burst back into the Flames' end on the transition and sent a pass to Alfredsson driving to the slot. With Flames defenseman Chris Butler providing a screen, the Senators captain snapped a shot into the top corner for his fifth goal.
Calgary tied it before the second period ended.
Anderson went behind the net to play the puck, but his pass was intercepted by Matt Stajan, who fired the puck into the slot where it was deflected in by Kostopoulos.
Calgary went 0 for 6 with the man advantage to fall to an NHL worst 2 for 40 on home ice. During a 64 second, two-man advantage, the Flames failed to record a shot. Ottawa was 0 for 4 on the power play.
NOTES: Calgary LW David Moss (lower body) didn't play, opening up a lineup spot for Stajan, who was a healthy scratch the past two games. ... Iginla, Rene Bourque, and Curtis Glencross share the team lead with five goals. Last place Columbus is the only other NHL team without a player with more than five. ... The last time Ottawa scored more than three goals against the Flames was in a 4-4 tie on Nov. 22, 2001. That was also the last time Alfredsson had scored against Calgary. He was blanked in 10 games since, his second-longest drought against any NHL opponent. Alfredsson hasn't scored in his last 12 games against New Jersey.