Sprint car racing’s top prize is up for grabs this week at the 40th annual Knoxville Nationals. The first of two rounds of qualifying is tonight. The event will draw about 20-thousand fans per night and will bring in millions to the community. Pat Boyle is executive director of the Knoxville Chamber of Commerce. An economic study about nine or ten years ago showed that the races brought in 10-million dollars.Boyle says more than just Knoxville benefits from the event as hotels around the area also fill up.Saturday night’s championship race will again be televised nationally by The Nashville Network. Boyle says says television over the last several years has served to increase the number of fans who want to attend the nationals.