Earnhardt is survived by his wife and four children, including his son Dale Jr.
‘Auto Racing’s Michael Jordan’
"We have lost our Michael Jordan, our Tiger Woods, and it's been a terrible day, it's left a black hole in this sport that we won't see filled for a long time," said H.A. "Humpy" Wheeler, president of Lowes Motor Speedway in Charlotte, N.C., and a longtime friend of Earnhardt.
Earnhardt's family was centered around auto racing. His father Ralph Earnhardt was a champion on small-track races, but never achieved success in higher-profile events such as NASCAR races.
Jerry Punch, a racing analyst for ESPN, said Earnhardt was protecting his teammates when the fatal accident occurred.
"He stayed there and ran a 180-185 mph screen," Punch noted.
Earnhardt was trying to block another driver, Sterling Marlin, from gaining on his teammates Earnhardt Jr. and Waltrip.
Marlin's car bumped his Chevrolet and set it spinning into the wall, where it was broadsided by Ken Schrader.
Accident Fuels Debate Over Safety
There have been two other fatalities from similar accidents around turns, raising concerns about a possible systematic problem.
The Lowes Motor Speedway installed a form of foam on the turn walls to try to prevent similar accidents.
Sunday's fatal crash is the biggest blow to the sport since Ayrton Senna, a three-time Formula One champion, died at Italy's San Marino Grand Prix in 1994.
NASCAR drivers Neil Bonnet and Rodney Orr were also killed in separate crashes in 1994, both while practicing for the Daytona 500.
Earnhardt himself had crashed at Daytona in 1997, flipping his vehicle but emerging without serious injury.
Too Much to Bear
For a racing community still healing from the loss of Adam Petty, the death of Dale Earnhardt was almost too much to bear.
Hours after the tragic event, a steady stream of devastated fans stopped at his race shop to mourn.
Jeff Goddard, an employee of Petty Enterprises, was one of them. Wearing a bright red Petty jacket, Goddard paced in front of the makeshift memorial created along the gate at DEI Inc.
“I just got in my car and drove and ended up here,” he said. “We kind of just got over the death of Adam, and now this. It’s devastating”
Petty, 19, was killed in a crash during practice at New Hampshire International Speedway last May. A fourth-generation driver, his death rocked the racing community. But it did little to brace anyone for the death of Earnhardt.
“No matter where it happens or how it happens or even how prepared you think you might be for it, losing somebody close to you hurts,” said Kyle Petty, Adam’s father.
ABCNEWS.com's Oliver Libaw and ABCNEWS Radio's Ed Dubrow and ABCNEWS' Ron Claiborne contributed to this report.