-- No tempers raged out of control and no sheet metal was mauled in retribution on the high banks of Dover International Speedway on Sunday, as stock-car racers heeded NASCAR President Mike Helton's pre-race command that "enough's enough" when it came to rough-housing on the track.

Jimmie Johnson drove off with the victory in the MBNA 400, holding off a spirited charge by his Hendrick Motorsports teammate Kyle Busch, to retake the points lead in the battle for the 2005 championship for the first time since July.

Following Johnson and Busch across the finish line was veteran Rusty Wallace, who vaulted to second in the standings as a result. At 49, Wallace is competing in his final NASCAR season, and he admitted that his strong showing Sunday, which puts him tantalizingly close to what would be his second NASCAR championship, has given him twinges of regret about his decision to retire.

"I'm driving better than I have in a long, long time," said Wallace, NASCAR's 1989 champion, "so it does make you think twice. But on the other hand, I've made the right decision. I want to go out on the top of my game, and I'm doing that right now."

Mark Martin came home fourth, turning in the best finish among the five Roush Racing drivers vying for the 2005 title. And pole-sitter Ryan Newman finished fifth.

The 400-lap race featured 15 lead changes among seven drivers but was hardly riveting, with single-car spins and blown tires bringing out most of the cautions. That said, the upshot was dramatic, scrambling the point standings and bunching up the front-runners for the title. With eight races remaining, the top six drivers in the standings are separated by just 23 points.

"You've got to believe that anybody is a threat," said Johnson, who won his third race of the season and the 17th of his career before a crowd estimated at 150,000.

It was a race in which drivers' fates were determined more by powerful engines and bad luck than by the ugly behavior and underhanded tactics that marred the previous week's NASCAR race at Loudon, N.H. Things got so out of hand in New Hampshire -- where one driver intentionally rammed another as payback for an earlier crash, another racer attempted the same, and innocent front-runners were nearly wrecked in the process -- that Helton stopped the race until tempers cooled.

Helton had more to say about the antics Sunday, reading a passage from NASCAR's rulebook that gave its officials unlimited authority to discipline any driver deemed "a threat" however they saw fit -- including suspending him for the season and revoking his license.

"We're going to step it up and do whatever we have to do to get it under control," Helton said, rulebook in hand. "Enough's enough."

With Newman's Dodge on the pole, the race got off to a clean, orderly start. His first challenge came from fan favorite Dale Earnhardt Jr., whose sub-par season shut him out of NASCAR's postseason title chase. Driving a lightning-fast, new Chevrolet, Earnhardt zoomed to second place only to slow suddenly with brake trouble. After stopping for repairs, he returned to the track just as fast but seven laps in arrears and was never a factor. "The only thing that sucks worse than a bad finish is a bad finish with a fast racecar," said Earnhardt, who finished 31st.

Tony Stewart, who entered the race with the points lead, had an equally miserable day. He started well back in the pack and struggled just to avoid being lapped. Then, after working his way toward the front, his crew broke the jack during a pit stop and he finished 18th, which dropped him to fifth in the standings.

Blown tires bit three Roush Racing teammates, spoiling the day for Greg Biffle (13th), Kurt Busch (23rd) and Matt Kenseth (35th).

Jeff Gordon's effort to salvage a disappointing season also met with bad luck. His Chevrolet shot up the track and into the concrete wall when Jamie McMurray spun just ahead of him in Turn 3 on Lap 293.

With 40 laps to go, the race shaped up as a battle among Johnson, Martin and Kyle Busch. The final pit stops proved pivotal. Martin's team gambled, opting to change just two tires so they could exit the pits faster and take the lead. The other front-runners changed four tires, confident that better grip would enable them to race harder down the stretch. They were right.

Johnson needed just one lap to zoom past Martin and retake the lead. Kyle Busch followed in his tracks, relegating Martin to third.

Joe Nemechek's crash with three laps to go forced NASCAR officials to extend the race so workers could clear the debris. Then came a green-white-checker restart that set up a two-lap shootout for the spoils.

Busch tried hard but couldn't get past Johnson. "He's a good enough driver where I knew it was going to be rough for me to do that," Busch said, "and I didn't want to hit him."

Jimmie Johnson, middle right, stands on his car and celebrates with his crew after his victory. Six drivers are within 23 points with eight races to go.