Schmaltz's decisive tally came during the sudden-death portion of the shootout, which lasted seven rounds. Blackhawks goalie Anton Forsberg proceeded to stop Mark Stone's attempt to seal the win.
Patrick Kane (23rd goal) and Artem Anisimov (16th) each scored in regulation for Chicago, which won for the second time in three games. The Blackhawks entered having lost nine of 10 (1-8-1) in February.
Zack Smith (fifth goal) and Matt Duchene (16th) had the goals for Ottawa. The Senators had won two of three coming in, but lost their second straight after a 5-2 setback at Nashville and fell to 6-4-1 this month.
Forsberg recorded 32 saves in the win. Mike Condon made 36 stops for Ottawa.
Chicago routed Ottawa 8-2 in their first meeting this season on Jan. 9, with Schmaltz and Jonathan Toews each registering two goals for the Blackhawks. Chicago improved to 9-2-1 in its last 11 versus Ottawa.
Senators center Ryan Dzingel returned to the lineup after missing two games due to a family issue. The Wheaton, Ill., native didn't find his way onto the scoresheet.
Kane's goal with 5:41 to go in the opening period put the Blackhawks on top 1-0. A trailing Kane took a backhanded feed from Vinnie Hinostroza in the slot and sent the puck trickling past Condon.
Not long after, Smith pulled the Senators into a 1-all tie at the 15:56 mark of the period after placing a rebound of Derick Brassard's shot from the circle past Forsberg.
Anisimov restored Chicago's one-goal lead when he directed a beautiful cross-ice pass from Kane past Condon with 14:08 left in the second.
But like the Blackhawks' first lead, this one didn't last long either, as Duchene fired a wrister past Forsberg glove-side with 7:59 to go in the middle period.
Ottawa returns home to face Tampa Bay on Thursday. Chicago wraps up its five-game homestand Friday against San Jose.
--Field Level Media
Ottawa | Chicago | |
Mark Stone 2 | Points | Patrick Kane 2 |
Matt Duchene 1 | Goals | Patrick Kane 1 |
Mark Stone 2 | Assists | Patrick Kane 1 |
N/A | Power Play Goals | N/A |
N/A | Short Handed Goals | N/A |
Mike Condon .947 | Save Percentage | Anton Forsberg .941 |
Mike Condon 36 | Saves | Anton Forsberg 32 |
Team | Shots | Goals | Power Play | Penalty Kill | Penalty Mins | Face Offs Won |
Ottawa | 34 | 2 | 0-1 | 2-2 | 4 | 27 |
Chicago | 38 | 3 | 0-2 | 1-1 | 2 | 31 |