Complex sentence: Mrs. Polinger was raised in Maryland and had always wanted to run a horse in the Preakness Stakes and this was her chance to do the next best thing, run a horse in the Dixie Handicap.
Split into simpler sentences: Mrs. Polinger was raised in Maryland and had always wanted to run a horse in the Preakness Stakes. This was her chance to do the next best thing: run a horse in the Dixie Handicap.