Derrick Rose scored 26 points while Joakim Noah recorded 18 and 19 rebounds for the Bulls (39-41), who built a 19-point lead through three quarters to cruise to victory.
"We really played hard, Noah told reporters. "We played the right way. "We followed the game plan and it was a question of the right intensity.
"I think we came with the right intensity tonight.
"I'm happy we got the W."
Toronto (38-42) lost their fifth successive game and are reeling in the absence of All-Star Chris Bosh, who suffered a facial fracture on Tuesday and will miss the rest of the regular season.
Andrea Bargnani and Sonny Weems scored 18 points each for the Raptors who have two games remaining and hold the tie-breaker over Chicago should they end with the same record, having won two of their three games this season.
The Bulls have capitalized on the collapse of the Raptors and put themselves back in playoff position despite a season that has included a 10-game losing streak and injuries to Rose and Noah.
Chicago fell to the NBA-worst New Jersey Nets on Friday but rebounded quickly and led for virtually the entire game on Sunday.
"They were better than us, obviously," said Raptors coach Jay Triano, summing up the loss that was a crushing blow to his already battered team who were without several injured players.
(Reporting by Jahmal Corner in Los Angeles; Editing by Greg Stutchbury)
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