DAYTONA BEACH, Fla. (AP) _ Dale Earnhardt Jr. was leading halfway through the Daytona 500 on Sunday, five years after his father died on the final lap of the same season-opening race.

Race favourite Jeff Gordon brushed the wall early and was way back.

Earnhardt was followed by 2003 series champ Matt Kenseth, 2004 series champ Kurt Busch, retiring driver Mark Martin and Jimmie Johnson.

Defending Nextel Cup champion Tony Stewart was passed for the lead on lap 47 and trying to keep from losing several spots when he tapped Gordon from behind. Both cars brushed the wall, but Gordon sustained much more damage.

Gordon, the four-time series champion, fell near the back of the field, making several pit stops in hopes of getting the car back into shape. He later told his team by radio that his transmission was missing a gear, making it nearly impossible to keep up during restarts.

Stewart, meanwhile, worked his way back into the top 10 about 20 laps later.

Contact between Jeff Green and Dale Jarrett caused a five-car pileup that took out Carl Edwards and Kyle Petty.