LONG POND, Pa. - Bobby Labonte and Tony Stewart crashed. Kurt Busch had transmission woes. Dale Earnhardt Jr. fought pain and an unruly car.

One by one, drivers in the top 10 in the Nextel Cup standings dropped out Sunday at Pocono Raceway, guaranteeing heated jostling for positions in the next six races.

There were changes everywhere in the standings, but the top.

Jimmie Johnson pulled off a clean sweep at Pocono Raceway, winning the Pennsylvania 500 on Sunday for his fourth victory of the season.

"I think we can win more races and be a serious threat for the championship at the end of the year," Johnson said. "A little luck will play in those final 10, but if it comes down to performance, I'll put my guys up against anybody."

Johnson said there was little use complaining about NASCAR's new points system that will leave him fighting for a championship instead of celebrating one near season's end. He figures the only solution is to keeping winning races.

"You might want to get all your smiles and good photos out of us now, because with 10 to go, it won't be the same," Johnson said.

The "Chase for the Cup" begins at New Hampshire International Speedway on Sept. 19.

Mark Martin was second, 2.138 seconds back. Kasey Kahne was third, followed by Greg Biffle and Jeff Gordon.

While Johnson cruised, many in the top 10 struggled, with Stewart, Kevin Harvick, Labonte and Busch all failing to finish, and Ryan Newman ending up 13th.

Nine spots in the top 10 juggled names.

Harvick fell from ninth overall to 10th after failing to finish a race for the first time since October 2002 in Atlanta. Labonte dropped from seventh to ninth overall, while Newman jumped from 10th to eighth.

Newman has a 52-point cushion on 10th place.

But it was those fighting for the 10th and final spot that made the most progress.

Jeremy Mayfield went from being 106 points behind No. 10 to 40 points back. Kahne jumped from 162 points behind to 69 and Martin from 192 to 89 out.

"It wouldn't surprise me if we went on and won the whole thing," said Mayfield, who finished ninth for his third straight top-10 finish.

Martin's second-place finish was his 18th top-five and 25th top-10 in 36 races at Pocono and kept him in contention after proclaiming himself eliminated at the same track seven weeks ago.

"That fact is a miracle," Martin said. "Now can we make it to the top 10? We all need to go win the Brickyard. That would make up for all the heartbreak we experienced this year."

For Johnson, losing out on a potential first points title would be heartbreaking.

Under the old points system, Johnson probably could have cruised toward his first career points title. Instead, he'll be lumped with the rest of the drivers in the top 10 to compete for the championship in the last 10 races of the season.

"I just have to deal with the rules the way they are and race as hard as we can every week," Johnson said.

Johnson started 14th and earned a $90,000 bonus from NASCAR for winning the race as the points leader. He's the first points leader to win in Pocono since Gordon in 1998.

With rain wiping out a practice session Saturday and shortening one Friday, qualifying was the only significant time for teams on the track before the race. Several drivers, including Gordon and Newman, complained their cars were too tight early in the race.

They probably would have all needed a near-flawless performance anyway to catch Johnson, who had his 12th top-10 finish in the last 14 races.

Still battling injuries from a fiery wreck, Earnhardt needed a relief driver for the second straight week. He gave way to John Andretti after completing 52 laps.

Andretti made another quick pit stop to readjust, but finished 25th after the car was black-flagged by NASCAR for not maintaining the minimum speed.

Johnson dominated almost from the start, taking the lead for the first time on lap 32. He led 124 laps and broke a recent trend at Pocono that saw 11 of the last 14 races won from a top-five starting position.

Not everything was perfect, though

Whoever said victory was sweet wasn't swigging Johnson's postrace champagne identified only with a Pennsylvania 500 label.

"It's not the tastiest of champagnes, but it will do in a pinch," he said.