You might think the world's most expensive car would be a new super car like a Bugatti Veyron or a shiny new Rolls Royce you wouldn't dare even think of breathing on, let alone driving.

But that title could go to a 1965 Shelby Daytona Cobra Coupe that once ran races and was used by one of its owners to make 300-mile daily round trips for business.

The iconic race car is expected to sell for $10 million to $15 million when it goes on the auction block in Indianapolis on May 15, prior to the Indianapolis 500.

The fully-restored car will be sold in a live TV auction on the Discovery Channel's "HD Theatre."

The car will likely surpass the U.S. record of $5.5 million for a 1966 Shelby Cobra 427 Super Snake. It could also set a new world record if it exceeds the $11 million paid last year for a 1961 Ferrari California Spyder.

What makes the vehicle so pricey is that it was the first U.S. race car to ever beat a Ferrari in world racing championships in Europe, winning the FIA GTIII championship at Reims, France, in 1965. It's was also hand-built and one of only six made.

The car has had several owners over its years, including one who drove it 300 miles round trip each day, in full racing trim, to collect the receipts from his six gas stations.