Johnson had shared the mark of seven wins on the concrete mile with Bobby Allison and Richard Petty.
"Truthfully, it was the first thought that went through my mind when I crossed the finish line," Johnson said. "It wasn't long after I thought about the impact of winning in the Chase."
Johnson's win bumped him from third to second in the Chase for the Sprint Cup championship standings. Matt Kenseth, who won the first two Chase races, holds an eight-point lead over Johnson as the Chase heads to Kansas for the fourth race.
Led by Johnson's fifth win, the entire top 10 was made up of Chase drivers. Joey Logano, Jeff Gordon and Kyle Busch rounded out the top five. Kevin Harvick, Kenseth, Ryan Newman, Greg Biffle and Clint Bowyer completed the top 10.
"You've got to win when you're at your best track," Johnson said. "We had to win here today. I think any points on the 18 or 20 would have been a very good day. Max points, it's an awesome day."
Not so much for Earnhardt, who had one of the fastest cars, but he missed pit road and gave up the lead early in the race. He had a strong enough No. 88 Chevrolet to get back into the race and contend for his first win of the season but couldn't pass Johnson.
"We left everybody in the mirror. We were clicking off some laps," Earnhardt said. "But just not fast enough to get to Jimmie."
Kenseth kept his points lead even as he fell short in trying to become the first driver to win the first three Chase races.
"Johnson led 243 of the 400 laps.
1. M. Kenseth 2,149
2. J. Johnson 2,141 -8
3. Kyle Busch 2,137 -12
4. K Harvick 2,110 -39
4. J. Gordon 2,110 -39
6. G. Biffle 2,108 -41
7. R. Newman 2,101 -48
8. C. Bowyer 2,098 -51
9. Kurt Busch 2,094 -55
10. Earnhardt 2,092 -57
11. C. Edwards 2,084 -65
12. J. Logano 2,083 -66
13. K. Kahne 2,071 -78