The USA Today newspaper says more than 20 sporsors have left the Busch series since the beginning of 2001.
Larry Camp, president of US-based marketing firm Camp and Associates, predicts that several of the 100 Busch series teams may fold.
But the director of the series Brian DeHart says he is optimistic that more teams will find sponsors. "We're in pretty good shape, along the same lines as we were in 2001," he said. "I feel pretty good that in the next couple of weeks, especially after we get through testing, guys will be able to show sponsors that they've got a real good quality team."
Sponsors part with about $2.5-$5million (EUR2.84-5.68m) a year to sponsor the Busch series, about half the amount they spend for the same package in the Winston Cup.
