Just as NASCAR evolved from its notorious backwoods past and earned respectability among the affluent crowd, something came loose in Turn 4.

That's how stock car drivers often describe a bad wreck or a mechanical problem when they're barreling around the track in search of fame and fortune at the finish line.

When that happens, it usually means the driver is out of the race and back in the garage with a broken car.

A similar catastrophe is about to happen to this All-American sport that has made its living off die-hard fans and corporate sponsorships that are drying up faster than a busted radiator.

NASCAR, the glittering spectacle of fast machines flashing by at 200 miles per hour, has suddenly seen the caution flag come out as the nation's economy slows down for a pit stop.

"There are pressures on certain revenue streams that are pretty obvious to us, sponsorship being one," NASCAR's chief executive officer, Brian France, said recently. "In certain markets attendance has definitely suffered."

Indeed, if things don't improve soon, stock car racing could be one of the first major sports to gear down and come to a screeching halt.

Wobbly wheels

Basically, this is a multi-car pileup.

All of those advertisers displayed so prominently on the cars that zoom around the track each weekend represent millions of dollars that have kept NASCAR on the rise in recent decades.

While race fans are said to be the most loyal to their favorite drivers and sponsors, many of these lucrative deals will no doubt start to disappear.

Combine that reality with the current panic among big automakers like Ford and Chevy and you can see the wheels of this industry starting to wobble.

"The basic rule of thumb is that the more a sport depends on corporate dollars, the more it feels an economic downturn, and this one is hitting NASCAR hard," said David Caraviello, a senior writer for NASCAR.com, who lives and works out of Charleston.

"There were a lot of worried people out there even before the recent news about GM and Ford. You usually see a flurry of announcements this time of year about which companies will be sponsoring which cars for the next year — but not this year."

Major shakeout

There's talk in the garages that several hundred crewmen will be let go once this season ends Sunday with the running of the Ford 400 in Miami.

The offseason, therefore, will be an intense time before the cars are slated to start the next 36-race schedule in February.

Those who follow the sport closely expect a major shakeout between now and then.

"Right now there are fewer than 30 cars that have full sponsorship secured for 2009," said Caraviello, a former Post and Courier reporter. "A lot of these mid- and lower-level teams without sponsors are talking about mergers."

In recent years, the racing game has seen the emergence of several super stock car teams like Hendrick Motorsports and Roush Fenway, which have big-money sponsors locked up in long-term contracts.

"I think these elite teams will weather this," Caraviello said. "But there are a lot of smaller operations scrambling for money, and some of them probably won't survive."