The Blackhawks, winners of three straight, were handed the Central Division minutes before the puck was dropped when Detroit lost at Philadelphia.
"I'd be lying to you if I said it wasn't our goal at the start of the year," Kane said. "It has been a long time coming. I was 4 years old the last time we won the division. It's a good accomplishment, but it's not really the accomplishment you want. The big goal is the big award at the end of the year."
The Blackhawks reached 49 victories to tie the team record set in 1970-71 and matched in 1990-91 -- before ties were broken in shootouts. It was their eighth straight regular-season victory over the Flames, and they reached 105 points to move within two points of first-place San Jose in the Western Conference.
The Blackhawks seem to be turning up their game and pace just in time for the playoffs. Prior to their current winning streak, they had lost three straight and were 2-5-2 in their previous nine.
"We knew we could be better," Chicago coach Joel Quenneville said. "We had more speed than a week ago. It makes a noticeable difference in the game."
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Chicago forward Patrick Sharp, who had several prime chances Sunday, noted the same improvement.
"It was always a goal of ours to win the division and we feel good about that," he said. "But we want to play our best hockey going into the playoffs. Lately, we're beginning to do that."
Ian White scored for the Flames, whose three-game winning streak ended. They are ninth in the Western Conference, two points behind Colorado for the final playoff spot with three games left. The Avalanche have four games remaining.
"The reality is we need to get help," Calgary coach Brent Sutter said. "It's not too hard to figure out the mathematics here. We've got to run the table and they can only get five points."
If the Flames can't control their fate, it's partly because they weren't in charge at any time against Chicago.
"We didn't help ourselves a bit," Flames forward Craig Conroy said. "We kind of just got behind the 8-ball early.
"We had chances, but I give them credit," he added. "Their goalie played well today. He made some big saves. Now we've got to win all three [games] and we need a lot of help."
Niemi was solid in his fifth straight start and ninth in Chicago's last 11 games, while Calgary's Miikka Kiprusoff blocked 27 shots.
The Blackhawks jumped ahead 2-0 in the first period when Niklas Hjalmarsson's shot narrowly missed the left side of the net, bounded off the back boards and to Kopecky, who tucked in a backhand shot from the right edge of the crease.
Brouwer cut across the crease and backhanded a rebound of Seabrook's shot with 54 seconds left in the period to make it 2-0.
Kane extended Chicago's lead to 3-0 with 4:28 left in the second when he beat Kiprusoff high on the stick side on a 30-foot shot from the slot. After White replied 62 seconds later, Byfuglien completed the scoring with 2:46 left in the third with a goal from the slot.
The Blackhawks' Central Division championship is their first title since moving into the United Center in 1994-95. ... Kane has 84 points, the most for a Blackhawk player since Tony Amonte in 1999-2000. ... Chicago D Kim Johnsson missed his 11th game with concussion-like symptoms. RW Adam Burish and D Nick Boynton were healthy scratches. ... Calgary's Christopher Higgins missed his 11th game and LW Curtis Glencross missed his ninth because of lower-body injuries. Flames C Daymond Langkow missed his seventh game and RW Brian McGrattan missed his third with upper-body injuries.