Claiming Crown preview days have been scheduled at four racetracks in anticipation of the main event, which is set for Aug. 4 at Canterbury Park in Minnesota. The preview days will feature races with conditions identical to those of the Claiming Crown.Turf Paradise in Arizona has slated three races for May 6. On June 2, Philadelphia Park in Pennsylvania and Lone Star Park in Texas will each offer six races. On June 2-3, Prairie Meadows in Iowa will have five races.Philadelphia Park was the first track to offer a preview day when it did so last year. This year, purses for the races will range from $25,000 to $50,000. At Lone Star, the purses will range from $15,000 to $35,000.Other preview days are in the planning stages in California, Florida, Illinois, and Kentucky.The Claiming Crown, now in its third year, is a series of six races worth $550,000. It is a project of Canterbury Park, the National Horsemen's Benevolent and Protective Association, and the Thoroughbred Owners and Breeders Association.