When NASCAR’s most popular driver wins its biggest race, the harmony is pitch perfect. On such rare moments, the roar of engines seems almost fit for a choir loft.

Dale Earnhardt Jr. claimed his second Daytona 500 last year, and in recounting what always is a complicated emotional experience for his family, he demonstrated why his popularity remained constant even when his results didn’t.

For beyond the accident of birth, Junior has a way of connecting with the people on the other side of the catch fence.

“My mind instantly went to every fan that’s standing in his living room jumping up and down and running out in the yard and hollering across the street to the neighbors,” he said recently. “I knew there were a lot of people happy about that day. It felt so good to be able to be a part of that.

“I wanted to win that race pretty bad. But going through that experience amplified (the desire) to go back and do it again. Because there’s nothing like it.” And to think some used to say that Junior didn’t want success on the track badly enough.

Junior is 40 years old and arrives at his 16th Daytona 500 at a point in life where he seems quite comfortable with his position in the sport, his competitiveness and the art of being his father’s son. Yes, it all fits him like the pair of jeans that is among the myriad items he pitches to his public.

His switch to the powerful Hendrick Motorsports team from his late father’s team in 2008, along with a four-victory 2014 (as many wins as his previous nine seasons combined) have left Earnhardt in a cheery mood.

“I’ve never had more fun driving a race car than I have in the last five years,” he said.

“I didn’t know I could have this much fun. Last year I felt like a kid. I had the same feeling I had when I would go down to Myrtle Beach and run my late model car or go to Nashville with my late model. We were on top of the world having so much fun. That freedom came back in the past couple years to just enjoy it, just release the pressure and have fun driving cars.”

Daddy Dale Earnhardt chased the 500 like Ahab did his whale. On his 20th try, he finally won. On his 23rd, the seven-time Cup champion died in a crash on the final lap. His son finished second that day, after navigating the backwash of the wreck.

Junior has won twice the Daytona 500s as his old man (although he remains a solid seven behind in series championships). For a track that holds such conflicting memories, it has been very good to this generation of clan Earnhardt. He has four second-place finishes in the 500, and a total of 11 top-fives in both the spring and summer races.

Thanks to all the hoo-ha around Hendrick teammate Jeff Gordon — on the pole Sunday, appearing in possibly his last Daytona 500 — Earnhardt will enter this race with the lowest profile possible. Nothing less than a historic last ride could turn Earnhardt into a secondary theme.

And because of the uncertainty surrounding his new support staff, his route to another season-opening trip to victory lane is not clear.

The season didn’t begin smoothly for the new combo of Earnhardt and crew chief Greg Ives. They were ordered to the back of the field in one of the two Daytona qualifying races after failing an inspection (the car’s front end was a fraction of an inch too low).

Such detail is supposed to be the air that Ives breathes. A former engineer for Jimmie Johnson, a crew chief in the lower-level Xfinity Series for Regan Smith and Chase Elliott, Ives was brought to the majors after Earnhardt’s long-time crew chief Steve Letarte left for the NBC booth. One of the qualities that first impressed Earnhardt was Ives’ slavery to minutia — one of his first acts was to list 20 small problems with Earnhardt’s non-racing show car.

“That’s my job: To be 100 percent perfect at all times,” Ives has said, setting the impossible standard. “Not because that’s required by anybody else other than myself.”

To be determined is how well driver and new crew chief sync up as far as prepping the car and racing it, coming up with a common language for going faster. As far as caring for the gear works inside the helmet, Earnhardt said he just may require less psychological support than good friend Letarte supplied.

“Maybe I’m mature enough as a 40-year-old to act like a man and be professional inside the car and not have to depend on Greg to boost me up,” Earnhardt said.

Earnhardt makes crossing the threshold of 40 sound almost uplifting.

There was a time, quite recently, when it was OK to wonder whether Earnhardt would even win another race. Fans kept cheering loudest for him during every driver introduction. And he kept going out and disappointing (winning just one race from 2007-11).

Now it’s safe to wonder again if he might claim a first Cup championship. He competed for one last year until being knocked out at Talladega, before the round of eight.

Maybe he’ll do it; the odds are greater that he won’t. But along the way he promises to appreciate any moment the most popular driver actually earns his applause.

“Dang right I do,” Earnhardt said when asked if he savors winning now more than ever. “Those few years when we struggled and couldn’t get it right … I didn’t know if we’d ever right the ship. I had such a good beginning to my career, and it was going to be so disappointing for it to fizzle out that way. I thought to myself, please, I got to figure out a way to do something to make me feel good about myself and my career.”

That much has been won before Earnhardt is even commanded to start his engine at Daytona.