Jimmie Johnson leads and Danica Patrick is still in the mix after a late caution flag for debris on the track in turn two.
When the green flag came out with six laps to go, Johnson was followed by defending Cup champion Brad Keselowski, Denny Hamlin, Greg Biffle and Clint Bowyer. Patrick is running sixth.
Defending champ Matt Kenseth had led more laps than anyone when, suddenly, his car began smoking on lap 149. He headed to pit road and it didn't take long for the crew to push him behind the wall, ruining any hopes of becoming the first back-to-back winner since Sterling Marlin in 1994-95.
Kenseth and his new teammates at Joe Gibbs Racing, Kyle Busch and Denny Hamlin, were actually running 1-2-3 when Kenseth had some sort of engine or transmission problem. Just two laps later, Busch's car also went out, smoking as well, sending the driver of the No. 18 machine storming through the garage, ripping off his racesuit.
"It's really unfortunate," Busch said. "We were running 1-2-3 and it felt like we were dropping like flies. Something inside the motor broke that's not supposed to break. It's a little devastating when you're running 1-2-3 like that. Hopefully the No. 11 (Hamlin) can bring it home."
Edwards was caught up in a crash heading into turn one at the Daytona 500, another case of simply being in the wrong place at the wrong time. Trevor Bayne bumped Brad Keselowski from behind, which sent the No. 21 car sliding sideways.
Stewart was 82 laps behind the leaders when he rolled out of the garage after an early crash. His frustration was never more evident than when he joined in the repair effort, banging on his No. 14 car with a hammer during the long stint in the paddock.
"To hell with the season," Stewart said. "I wanted to win the Daytona 500. We had a car that we could pass with today. We were passing cars by ourselves. I was so happy with our car, was just waiting for it to all get sorted out again. I don't know what started it, but we just got caught up in another wreck."
Stewart's misfortune came a day after he won the lower-division Nationwide race — his 19th career triumph at Daytona.
While there's nothing unusual about Kenseth leading at Daytona, where he's won two of the last three years, it's a bit jarring to see him doing it in the No. 20 car.
Kenseth had spent his entire Cup career driving the No. 17 machine for Roush Fenway Racing, but he switched to Joe Gibbs Racing this season. He's got a new car, a new number, a new sponsor and a new team.
The first woman to start from the pole at the Daytona 500 has become the first female to lead a lap in a NASCAR Cup race.
Patrick sent the huge crowd into a frenzy when she snatched the lead from Michael Waltrip on lap 90 after a series of pit stops under yellow. She led two laps before Denny Hamlin surged to the front.
But Patrick has shown her qualifying run was no fluke. She's got a strong car and has been in the top 10 all day as the 200-lap race approaches the midway point.
Patrick switched to NASCAR last year after becoming the first woman to lead laps at the Indianapolis 500, as well as being the first to win an IndyCar race.
In the strangest part of the buildup to the Daytona 500, Mr. Cent brought back memories of Joe Namath's awkward attempt to plant one on Suzy Kolber when he tried the same move with Andrews on pit road.
Former 500 winners Kevin Harvick, Tony Stewart and Jamie McMurray were caught up in the crash on lap 33. So was defending Sprint Cup champion Brad Keselowski.
The melee began coming through the tri-oval when Kasey Kahne's car began to slide across the track after appearing to get bumped from behind by Kyle Busch.
At least two other drivers also got caught up in the mess: Juan Pablo Montoya and Casey Mears. Joey Logano made a great move to dodge the spinning cars.
HANG ON TIGHT: From one defending champion to another, Brad Keselowski had a piece of advice for Daytona 500 starter Ray Lewis:
The retired Baltimore Ravens star served as honorary starter for the Daytona 500. Lewis waved the green flag without incident Sunday to start the "Great American Race."
"Brad texted me on the way in, the one rule is, don't drop the flag," Lewis said before the race. "I'm going to squeeze the flag very hard. I want to watch this and be a part of it. To be here is an awesome experience."
Lewis was one of several stars at Daytona International Speedway. Rappers T.I. and 50 Cent attended NASCAR's season opener, which has Danica Patrick starting on the pole.
Oscar-nominated actor James Franco was the grand marshall and said, "Drivers and Danica, start your engines!" The Zac Brown Band played a pre-race concert in the Daytona International Speedway infield. Band member Clay Cook performed the national anthem.
Retired baseball pitcher Tom Gordon, comedian Drew Carey, and Wes Welker and Steve Spurrier also were in attendance.
Lewis called Keselowski on the eve of the 2012 season finale at Homestead-Miami Speedway and left him an inspirational voice message. Keselowski also often listens to Lewis' motivational speeches before races.
"I caught a glimpse of how he always watched my videos and it really inspired him," Lewis said. "That's when me and him really started having conversations with each other, and from there it just turned into a friendship. I send him motivational things, and heads-up on what I am doing, that's where the relationship has gone."
DANICA DROPS BACK: Danica Patrick made history by becoming the first woman to start from the pole in a NASCAR Cup race.
Choosing the outside spot on the front row, Patrick gave up the lead to Jeff Gordon on the very first lap, missing out on an early chance to become the first female to lead a Cup lap.
Patrick went on the radio before the race to thank her crew for giving her such a strong car. "I'll do the best job I can to do my end of the deal today," she said. "All in all, thank you for everything. You guys are awesome."
Later, Patrick sent the huge crowd into a frenzy when she snatched the lead from Michael Waltrip on lap 90 after a series of pit stops under yellow. She led two laps before Denny Hamlin surged to the front.
Of course, this year is different. Danica Patrick is the first woman to start from the pole in a Cup race, and Franco hinted beforehand that he was planning an audible. As unpredictable as ever, he passed on a chance to copy the command that was used when Patrick raced in the Indianapolis 500, "Lady and gentlemen, start your engines."
One day after a harrowing crash injured dozens of fans in the stands, those same seats are filling up for the Daytona 500.
"These should be good seats," said Rick Barasso, as he settled into a spot that was right in the danger zone when Kyle Larson's car slammed into the catch fencing on the final lap of a Nationwide Series race Saturday. "I mean, what are the chances of it happening again?"
That seems to be the attitude of the fans heading into the Daytona 500, the season-opening Cup race and biggest event on the NASCAR schedule. Most people say it's worth the risk to sit next to the ear-rattling action — no more than 20 feet away for those in the first row. They love to hear the engines, smell the exhaust, and feel the wind whipping in their face as 43 cars go by at nearly 200 mph.
Raymond Gober returned to the same location where he was nearly struck by a bolt from Larson's car. He scooped up the debris as a souvenir, though he acknowledged being a little nervous about his seat on the back row of the lower level. He even considered wearing his motorcycle helmet to the 500, but figured "everybody would start laughing at me." Next year, he plans to buy an upper-level seat in the main grandstand.
There are grim reminders of what happened Saturday: a bloody spot that had been washed down (not entirely, though), a tire mark on a seat, another seat that was partially bent from getting struck by that same tire.
EDITOR'S NOTE — "Daytona 500 Watch" shows you the Daytona 500 and events surrounding the race through the eyes of Associated Press journalists. Follow them on Twitter.
