What is NASCAR superstar Dale Earnhardt Jr.'s net worth? And where did it all come from?

"Dale Jr.," as he's known, is the son of the late, famed NASCAR driver Dale Earnhardt, who was killed in a 2001 crash at the Daytona International Speedway. Fittingly, Dale Jr. has won the Daytona 500 twice since joining NASCAR's top-level series full-time in 2000.

While he has yet to win NASCAR's Sprint Cup championship, Dale Jr. has been voted "Most Popular Driver" by racing fans every year since 2003. That popularity has translated into a lucrative stream of income to add to his substantial salary and race winnings.

So what's his net worth and where did it come from?

Checkered flag waving at a car race.

Image source: Getty Images.

Where Dale Earnhardt Jr.'s income comes from

Like most racing drivers, Dale Jr. has two principal sources of income. First is the money paid to him by the team that owns his car, Hendrick Motorsports. That includes a hefty salary, as well as a share of the cash prizes from race winnings.

He also, like most big-name racers, makes a substantial income from licensing and product endorsements. That income is particularly substantial in Dale Jr.'s case, thanks to his large and enthusiastic fan base. He also has some outside business interests, including ownership stakes in a racetrack, a media production company, and two auto dealerships in Florida.

The upshot? A large income -- and a hefty net worth by NASCAR standards. Several sources, including TheRichest.com, estimate Dale Earnhardt Jr.'s net worth at about $300 million.

Dale Jr.'s sponsors include General Motors (NYSE:GM) -- like his late father, he has had a long association with GM's Chevrolet brand. Other big names include Nationwide Mutual Insurance, PepsiCo (NASDAQ:PEP) brands Mountain Dew and AMP Energy, Unilever (NYSE:UN) brands Breyer's, Hellmann's, and Suave, and auction site eBay (NASDAQ:EBAY). (Earnhardt has described himself as an "eBay addict.")

What does all that add up to on an annual basis?

Endorsements have made Dale Jr. NASCAR's top-paid driver

In its most recent list of the world's highest-paid athletes, Forbes magazine ranked Earnhardt 28th, with earnings from mid-2013 to mid-2014 of $25.9 million. According to the magazine, that encompassed $14.9 million in salary and winnings and $11 million from endorsements.

That's enough to make Earnhardt the best-paid driver in NASCAR's top series, according to Forbes, even though others have won far more races. But his popularity pays off, year after year: $11 million in endorsement income is huge for a NASCAR driver. 

By comparison, the telegenic and popular Jeff Gordon made just $5 million during the same period. NASCAR drivers as a group struggle to find mass-market appeal beyond racing fans, but Dale Jr. has managed it better than most.

That $11 million was actually down a bit from his haul in earlier years: Forbes said he made $13 million in endorsements in 2013 (and $25.9 million in total income), and about the same amount in 2012. That was far ahead of second place Jimmie Johnson, who reeled in $6.7 million in endorsement income in 2013. 

And he's been earning at that level for quite a while: The 2004 edition of Forbes' list put his income for that year at $20.1 million, tops among NASCAR drivers and 18th among all pro athletes.

"No plans" to retire -- but he'll be in great financial shape when he does

Earnhardt's teammate at Hendrick Motorsports, Jeff Gordon, is set to retire from full-time racing after this season, but Dale Jr. has made it clear he's in no hurry to follow. He's only 40, after all, in a sport in which many drivers have remained active well into their 50s, and he has been fortunate to escape serious injury during his career.

Earnhardt's lucrative endorsement income and string of profitable side businesses suggest strongly that -- unlike too many pro athletes -- he has plenty of business savvy. He's probably also receiving (and, importantly, heeding) good financial advice. 

Should he choose to retire anytime soon, the income streams from those side investments should keep him living very comfortably. It's a fair bet that he'll add to that hefty net worth total for many years to come.