Kawhi Leonard got some help from his teammates to stay close and then finished it off himself.
"Just really growing up learning from great players, I was fortunate enough to be on some good teams early," Leonard said, "so I was able to see defenses and go on deep playoff runs and I feel that helped me out today."
Marc Gasol scored 16, Kyle Lowry had 14 and the Raptors rebounded after consecutive losses to reclaim home-court advantage.
"We needed some punch around the roster," Raptors coach Nick Nurse said. "It was a different mentality. Guys were looking to shoot, taking the first shot that was there."
Game 5 is Tuesday night in Toronto.
Jimmy Butler scored 29 and JJ Redick had 19 for Philadelphia. The 76ers are trying to reach the conference finals for the first time since Allen Iverson led them to the NBA Finals in 2001.
Toronto, which earned the No. 2 seed after winning 58 games, has been bounced out in the semis two straight seasons.
Joel Embiid struggled after scoring 33 points in Philadelphia's 21-point victory in Game 3. The All-Star center played through an illness and only had 11. Sixers coach Brett Brown said Embiid texted him early in the morning saying he wasn't sure if he could play.
"To his credit, he willed his way through it," Brown said.
Butler banked in a 3-pointer from the top of the circle as the shot clock expired after briefly losing the ball to give the Sixers an 84-81 lead in the fourth. But Gasol answered with a 3 to tie it and the Raptors went up 89-85 on Leonard's jumper. Butler and Leonard traded a pair of free throws before Redick hit a 3 to cut it to 91-90 with 2:07 left.
Following a turnover, Embiid missed a layup. Leonard then nailed a step-back 3 to put Toronto up 94-90. Danny Green made four free throws in the final minute to ice it.
Brown called Leonard's 3-pointer a "backbreaker" and compared his ability to create his own shot to Kobe Bryant. The 3 came right before the shot clock expired and Leonard had Embiid in his face.
"I came off a pick-and-roll. They were switching. Embiid is a good defender, long, and I just wanted to get it to the back of the rim," Leonard said.
Playing before a raucous crowd, the Sixers failed to take control of the series and now must win at least one more game on the road to advance.
"We got humbled," Butler said.
Serge Ibaka made the defensive play of the game in the second quarter, racing back down the floor to reject Tobias Harris during Philadelphia's 3-on-1 fast break. But the Raptors missed a shot on the opposite end and Embiid answered with an emphatic dunk.
Later in the quarter, Embiid blocked Ibaka and found Ben Simmons for a dunk. Embiid blocked Ibaka again 35 seconds later and Butler hit an 11-footer. Butler's 3-pointer with a second left in the second quarter got the Sixers within 47-45 at halftime.
Leonard scored six points during a 13-0 run in the first quarter to help the Raptors take a 22-11 lead. But the Sixers outscored Toronto 10-2 to cut the deficit to 24-21 after one.
Former Phillies manager Charlie Manuel and All-Star outfielder Shane Victorino of the 2008 World Series championship team rang the ceremonial Liberty Bell to start the game. ... Sixers Hall of Famer "Dr. J" Julius Erving sat in a suite. ... Eagles All-Pro center Jason Kelce and Pro Bowl tight end Zach Ertz sat courtside and Hall of Famer Terrell Owens received the loudest ovation in the "circle of stars."
Raptors: Only lost three straight games once during the regular season after a 12-1 start. ... Pascal Siakam played 28 minutes after being doubtful because of a right calf injury. He started 0 for 8 before making his first basket with 4:15 left in the third quarter. He finished 2 for 10. ... Leonard had 14 rebounds.
76ers: Embiid only took four shots in the first 32 minutes. He missed three straight free throws at one point in the fourth quarter. ... Harris had 16 points but shot 7 for 23, including 2 for 13 from beyond the arc.
Game 5 is Tuesday in Toronto.