It will take more than involvement in a fatal car crash to make sponsors think about leaving one of NASCAR's best pitch men, experts tell CNBC.
On Saturday, the vehicle driven by three-time NASCAR Sprint Cup champion Tony Stewart ran over a 20-year-old racer who was walking on the track during a sprint car race, killing the opponent. The incident has highlighted some racers' penchant for walking out of their cars and onto the track in anger, as apparently happened on Saturday.
But the crash could also spell changes for Stewart, who is one of NASCAR's most popular drivers, and who appeared to actually hit the throttle as he struck Kevin Ward Jr., according to some witnesses quoted by The New York Times.
Investigators say he is cooperating, and there is no evidence against him.
Unless he is convicted of a felony, Stewart probably will not suffer commercially, experts told CNBC.
"I don't think that there are people out there who would stop supporting [a company] because of its relationship with Tony Stewart," said Ramsey Poston, a former NASCAR executive and president of public relations company Tuckahoe Strategies. "I just don't see it rising to that level at all."
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In fact, Poston said, Stewart is so valuable to his primary sponsors, which include Bass Pro Shops and Mobil 1, that they will be very careful before breaking from the lucrative partnership.
"Sponsors depend on drivers who can carry the message, help develop a brand, and sell a product. And there are few drivers who do that better than Tony Stewart because of his passion and because he is genuine," Poston said.
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Stewart's sponsors should take a wait-and-see approach, said Bill Glenn, president of The Breakout Group, a consulting firm specializing in sponsorships. Without any legal trouble for Stewart, the companies attached to him cannot immediately know the public relations effects, he said.
Somewhat paradoxically, the crash could even be spun as a positive for the sponsors if they could become involved in any subsequent efforts to make racing safer, Glenn said.
This was not Stewart's first accident while driving sprint cars—which differ significantly from NASCAR stock cars and are often raced on short, dirt courses. He broke his leg during a race last year, forcing him to lose out on the remainder of the NASCAR season.
There were not any public consequences for Stewart after that crash. "Even though he was not on the track, he was still very visible in the sport," Poston said.
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As independent contractors, drivers and teams are not required to disclose how much they make from sponsorships, Poston said. But some estimates have put deals with primary sponsors, which get prime branding locations on the cars and uniforms, at $20 million for year-long contracts.
A spokeswoman from Bass Pro Shops directed CNBC to a statement on the company's Facebook site, declining to comment further. In part, that statement said, "We send our thoughts and prayers to the family and friends of sprint car competitor Kevin Ward Jr. and also to Tony Stewart and everyone at Stewart-Haas Racing."
In an email, an ExxonMobil spokesman wrote: "Regarding the tragic event that occurred this past weekend at Canandaigua Motorsports Park, our thoughts and prayers go out to all involved and to the loved ones of Kevin Ward, Jr."
"There aren't words to describe the sadness I feel about the accident that took the life of Kevin Ward Jr.," Stewart said in a statement.
—By CNBC's Everett Rosenfeld