It marked the first victory for his first-year team, Stewart-Haas Racing. It also was the first time his business partner, Gene Haas, was at the racetrack to see the team in action.
Stewart made a startling pass of Matt Kenseth with two laps to go in the nonpoints race, leading the final two laps in the winners-only race.
Haas formed the new team a year ago while in a federal prison. He spent 16 months in jail for tax evasion.
"The response is awesome," Stewart said. "The gamble was for Gene Haas. He's not going to miss another race. He gets here for his first one and we win."
Kenseth held on for second, followed by Kurt Busch, Denny Hamlin and Carl Edwards.
The race featured 21 cars. Most were winners from the 2008 and 2009 seasons. Sam Hornish Jr. and Jamie McMurray got into the main event by finishing first and second, respectively, in a 40-lap qualifying race. Rookie Joey Logano was voted in by fans.
The 100-lap event was broken into segments of 50, 20, 20 and 10 laps.
Jimmie Johnson started on the pole and he led every lap in the first segment. Kurt Busch finished second, followed by Jeff Gordon.
Kyle Busch's team changed only two tires after the first segment and shot to the front for the second segment. Johnson's team changed four tires, dropping him back to fifth.
Track position proved invaluable as Busch led all 20 laps in the second segment. Matt Kenseth was second, followed by Johnson.
Busch and Kenseth didn't stop at the end of the second segment so they could maintain their place at the front of the pack. Johnson was in one of the few cars that stopped, and it dropped him back to 14th place.
Hornish lost control on the second lap after the re-start. His car bounced into Greg Biffle's Ford, sending both into the first turn wall.
Kyle Busch's car bobbled coming off the second turn on the 10th lap of the third segment, allowing Gordon to make the first green-flag pass for the lead. Gordon easily won the third segment, while Kenseth was second, Kurt Busch was third and Kyle Busch was fourth.
There was a 10-minute break before the final 10 laps. The lineup for the final sprint was determined by the finishing order of the third segment.
Kyle Busch got a clean restart with eight laps remaining, but Kenseth got even with him a lap later.
While they fought for the front, Stewart got into contention. A caution for debris with five laps to go stacked up the field for the fourth re-start in five laps.
Kenseth led, but Stewart completed the surprising move with two laps to go, triggering a massive celebration along pit road.
Earlier, David Stremme started on the pole for the Sprint Showdown, the 40-lap qualifying race.
Hornish passed him with 15 laps to go and ran away to an easy 200-yard victory. McMurray passed Stremme to finish second.
"It went as well as I could have imagined," Hornish said.
Reach Don Coble at email@example.com