TwinSpires.com will hold an inaugural Royal Ascot Challenge Series, which will offer horseplayers opportunities to compete for cash prizes as well as potential seats at upcoming tournaments, the company announced Thursday. The first four tournaments, scheduled for Tuesday, June 17, through Friday, June 20, will serve as Royal Ascot "feeders" for the grand finale, the Royal Ascot Challenge held Saturday, June 21. Prizes for the Royal Ascot Challenge include cash and a potential seat in the upcoming Stephen Foster Betting Challenge June 28. "Each year American horseplayers have become increasingly...