Topeka ? Kansas Speedway added another incentive Wednesday in its bid to get the contract to manage the state-owned casino in Wyandotte County: a promise to bring in thousands of recreational vehicle users each year to a rally that would generate millions in revenue.

The speedway has a letter of commitment from Camping World, the world’s largest retailer of RV equipment, to hold the annual “Heart of America RV and Outdoor Rally” there starting in 2010, Speedway President Jeff Boerger said. The rally would bring at least 6,000 people to the area, he said, and generate an annual economic impact of some $10 million.

Boerger said the rally, like the promises of a new track and a second NASCAR Sprint Cup race, is contingent on the state choosing Kansas Entertainment LLC partnership over three other bidders that want to build and manage the state-owned casino in Wyandotte County. The speedway is part of that partnership.

A 2007 state law provides for four casinos, including one in Wyandotte County. The law calls for the Lottery Gaming Facility Review Board to choose the winner based on which applicant would bring the most revenue to the state, increase tourism and be in the state’s best interest.

Boerger’s announcement came a day after he promised that the speedway would build a 2 1/4-mile road course in its infield, designed for the Grand-Am Rolex Sports Car Series and competition by various sports car clubs.

Two weeks ago, the speedway offered to seek a second NASCAR Sprint Cup race if Kansas Entertainment, of which it is a part, gets the 15-year casino contract.

Kansas Entertainment’s plan would put a $705-million Hard Rock Hotel and Casino at the No. 2 turn of the 1 1/2 mile D-shaped oval track.

The other bidders for a Wyandotte County casino are Golden Heartland Inc., Legends Sun and Pinnacle Entertainment Inc.