The Racing Association of Central Iowa has offered to purchase Prairie Meadows Racetrack and Casino for $150 million. RACI, a non-profit organization that currently runs the Altoona track, would pay Polk County $15 million a year for 10 years, according to its proposal."We gave them what we consider is an offer that we can live with," RACI chairman Jim Rasmussen told the Des Moines Register. "They get a revenue stream -- guaranteed -- for 10 years."The racing association offered the county $14.5 million a year last fall in preliminary discussions on a rental agreement. Rasmussen told the newspaper he doesn't recall the offer, but some county officials asked why they should sell the track when they can rent it at a comparable cost."We're probably better off staying with a lease," said county supervisor Robert Brownell, who morally opposes the county's involvement in gambling. "My constituency expects if we're going to sell this thing, we've got to get a fair return. As far as I'm concerned, we're not there yet."The county plans to build a $208-million Iowa Events Center using gambling revenues rather than tax dollars. Figures show the racing association's proposal would provide only about $1 million more than the cost of the Events Center over a 15-year payment plan.The county is expected to make an official response to RACI's offer Nov. 21.