Oklahoma Gov. Brad Henry signed a bill Monday that allows electronic gaming machines at three racetracks in the state. A bill-signing ceremony was scheduled for Tuesday.Horsemen in Oklahoma have estimated purses will increase by $30 million with the devices at Remington Park, Will Rogers Downs, and Blue Ribbon Downs. The law allows for the tracks to have class II electronic games, the same as Oklahoma Indian casinos, and allows for some non-house banked card games, the Associated Press reported.Remington Park in Oklahoma City, which is owned by Magna Entertainment Corp., is in line to house 650 electronic gaming devices, the most of any track. Corey Johnsen, a regional vice president for MEC, has estimated Remington's daily purses would average over $200,000 when the machines are operational, which could be as soon as Sept. 1.