Updated

Bristol, TN (SportsNetwork.com) - In a race that featured five hours of rain delays and concluded with a confusing caution and the skies opening up again, Carl Edwards won Sunday's Food City 500 at Bristol Motor Speedway.

Edwards grabbed the lead with 78 laps to go when he opted not to pit while most of the other front runners came in for new tires. He then held off the field following a restart with less than 40 laps remaining. Edwards had a more than two-second lead over second-place runner and Roush Fenway Racing teammate Ricky Stenhouse Jr. with just over two laps left when the caution lights around this 0.533-mile, high-banked oval came on for no apparent reason. Moments later, heavy rain fell on the track, forcing NASCAR officials to end the race under caution.

Shortly after the race concluded, NASCAR vice president of competition Robin Pemberton explained what triggered the final caution at the end of the race, saying, "It appears that in the flag stand one of the flag people had leaned on the switch that is the manual override for the caution lights, and so that happened."

Pemberton also said, "When the flag stand realized that the caution lights were illuminated, the flag man threw the flag, and then after that happened, we froze the field from the tower. It appears that in, not all, but most of the flag stands have a manual override for the caution lights, and due to the weather and due to other things, there's an area that it couldn't have been -- it wasn't secured properly, and the flag person leaned against the switch and turned the caution lights on.

"We tried to turn them off, and we realized that the override switch was on and they were hung on caution. It was a stupid error."

The rain prevented any attempt at a green-white-checkered finish. The caution came before the final lap.

Edwards claimed his 22nd career win in the Sprint Cup Series, including his third at Bristol. His previous victories here occurred in the August night race (2007 and '08).

Edwards also became the fourth different driver to win in as many races this season. He joins Dale Earnhardt Jr. (Daytona 500), Kevin Harvick (Phoenix) and Brad Keselowski (Las Vegas) as those drivers who have all but guaranteed themselves a berth in this year's Chase for the Sprint Cup championship.

"I guess I'm part of a group of guys that can go have some fun and focus on the final 10 races to get to this championship," Edwards said. "I've been a little bit jealous of those guys who have wins this early in the season. I was thinking, 'I can't imagine what it must be like to be able to come to the racetrack like this and have all that pressure off of you.' So now we'll get to go have some fun. I'm really excited about the next 22 races."

Stenhouse, who was the rookie of the year in Sprint Cup last year, finished a career-best second. Stenhouse, Aric Almirola and Denny Hamlin, the pole sitter, also did not pit during the final round of stops.

"We stayed out there and kept our track position and ended up second, so it was cool to have a one-two finish for Roush Fenway this weekend," Stenhouse said.

Almirola's third-place run was his best finish in the series as well.

"It's frustrating because I had one shot to race Carl for the lead, and these races are so hard to win," Almirola said. "I'm not disappointed at all with third, but when you see it and you can taste it and it's that close, you wonder what could have went different."

Tony Stewart was fourth, and Marcos Ambrose, who is Almirola's teammate at Richard Petty Motorsports, crossed the line in fifth.

Ford claimed four of the top-five finishing positions.

"Huge day for Ford," Edwards said. "People were talking a lot about how Fords are running so great on Friday, and it wasn't our Fords. It was not our Roush Fenway Fords. We've been struggling lately, and for us to come out of here with a win and to run so well with a number of the Fords out of our shop, that was big."

Matt Kenseth, who won at Bristol last August, led the most laps with 165. He was leading the way when the race was stopped after 124 laps were completed because of inclement weather. The second rain delay lasted 3 hours and 19 minutes, and the event resumed under the lights at 7:15 p.m. local time. The start of the race came roughly 1 hour and 45 minutes after its scheduled time of 1:15 p.m.

On lap 156, Cole Whitt and Danica Patrick got together and made contact with the wall. After the caution lights came on, Timmy Hill did not slow enough and drilled into the back of Kenseth, who was running second at the time. The front end of Hill's car was severely damaged, while Kenseth sustained minimal damage to rear of his vehicle, forcing him to pit multiple times during the caution and dropping him to 29th in the field.

"This place, things happen really quick," Hill said. "I saw the 26 [Whitt] spin down in turns 1 and 2, but by the time I got the communication info, it was too late. I was on the brakes hard, and everybody was checking up. I got right into the back of the 20 [Kenseth]. It was just a late call, and I didn't have any reaction time. It's all on me."

Kenseth rebounded nicely and grabbed the lead again after a restart on lap 285. While running in third with just under 100 laps to go, Kenseth slid two separate times and brushed the wall. He had dropped to 13th and ended up finishing in that position.

Hamlin finished sixth, followed by Jeff Gordon, Kasey Kahne, who won this race one year ago, Brian Vickers and rookie Kyle Larson.

After placing either first or second in the first three races, Earnhardt finished 24th, one lap behind. Keselowski moved into the points lead following his 14th-place run, while Earnhardt trails Keselowski by 10 points.