FRANKFORT, Ky. (AP) — Legislation is being prepared to preserve historical racing operations that serve as a crucial revenue source for Kentucky’s horse tracks. Sen. John Schickel says he’ll introduce the measure when lawmakers resume their session next Tuesday. He says it will come up two days later in the Senate Licensing and Occupations Committee that he chairs. Senate President Robert Stivers will co-sponsor the bill. The state Supreme Court has ruled at least some forms of historical race wagering don’t meet pari-mutuel wagering standards. Historical racing features slots-style machines allowing people to bet on randomly generated, past horse races.