Dale Earnhardt Jr. is enjoying prime time in his NASCAR career

A NASCAR career on the upswing has Dale Earnhardt Jr. sounding content as he nears his 40th birthday.

“I feel physically and mentally 10 years younger than that,” Earnhardt said as he prepared for Sunday’s Chase for the Sprint Cup opening race at Chicagoland Speedway.

“I still enjoy what I do and had the best time driving race cars this year,” he said. “[That] surprised me because I hadn’t been having a good time several years ago and I didn’t know if that was ever going to change.”

Based on Friday practice laps, Earnhardt will have a respectable start in the seventh row in Sunday’s 43-entry race at Chicagoland. He missed a chance for a better spot when rain canceled official qualifying runs.

Still, Earnhardt is in the midst of his best run in several seasons. He essentially clinched one of 16 Chase playoff berths by winning the year’s first race — the Daytona 500 -- and then claimed two more Spring Cup victories through the next 25.

Three trips to the winner’s circle this year are the most for him since he made six in 2004. Earnhardt also has been consistently near the front with 11 top-five finishes and 16 among the top 10 this year.

He enters Sunday’s race tied for second with Jeff Gordon behind series leader Brad Keselowski.

“This is a big deal … and I really hope we can make our fans proud, make all our supporters proud of the job we do,” Earnhardt said. “There’s a lot of pressure. A lot of people are really relying on us and depending on us and we want to be able to deliver.”

Earnhardt opens the Chase on a track where he has had some success. He was a Chicagoland winner in 2005 and has three top-five finishes in 13 races here in NASCAR’s top series. In 2013, engine trouble knocked him out after 224 laps.

“We didn’t have a good run at Chicago” last year, he said. “But the rest of the Chase we had a great little string of finishes.”

Earnhardt drives the No. 88 National Guard Chevrolet for Hendrick Motorsports, the NASCAR powerhouse team that includes Chase drivers Gordon, six-time champion Jimmie Johnson and Kasey Kahne.

He’s the latest generation of racing royalty, part of a family that includes grandfather Ralph Earnhardt, a 1956 NASCAR Sportsman champion and part of the inaugural 2010 NASCAR Hall of Fame class.

His father, Dale Earnhardt Sr., is one of the sport’s legends with seven NASCAR titles and 76 victories in NASCAR’s top series before his death in a wreck at age 49 in 2001.

Dale Earnhardt Jr. picked up the racing mantle at age 17. By the time he turned 24, he was driving in NASCAR. He has compiled a run of 531 races, and in that span he has claimed 22 victories and 126 finishes among the top five along with 13 pole positions.

While he has qualified for the Chase seven times, including each of the last four years, a title in NASCAR’s top series remains elusive.

But he long has been a champion among fans, awarded the circuit’s Most Popular Driver award yearly since 2003.

Earnhardt turns 40 on Oct. 10, the day before the 10-race Chase for the Cup series hits the midpoint at Charlotte Motor Speedway.

“You don’t have much of a choice with your age when you hit these milestones,” he said. However, “I feel really fortunate. I feel lucky to still be enjoying what I do and the passion is still there.

“I’m having as much fun as I’ve ever had.”

Harvick wins Nationwide race

Kevin Harvick earned his fourth Nationwide Series win of the season Saturday with a victory for JR Motorsports at Chicagoland Speedway.

Harvick took the lead on a two-tire pit stop 39 laps from the finish when Kyle Busch took four tires. Harvick led for 43 laps in all.

Kyle Larson finished second and Busch settled for third after leading 141 of the 200 laps.

Ryan Blaney was fourth, followed by Trevor Bayne.

Nationwide points leader Chase Elliott finished 10th and lost a little ground in the championship race to JR Motorsports teammate Regan Smith, who was seventh. Elliott’s lead is now 18 points.

The victory was the ninth this season for JR Motorsports, and Harvick tied Brad Keselowski for most wins in a season for the team.