Who says politics isn't a circus? Kristin Davis, the one-time Manhattan madam who says she supplied call girls to El- iot Spitzer when he was New York's governor, shares a stage tonight with state Attorney General Andrew Cuomo and all the o ther candidates in the only debate of New York's gubernatorial race. Davis is running for governor as the candidate of the Anti-Prohibition Party. She was guaranteed a place tonight when Republican Carl Paladino demanded that Cuomo debate all the third-party hopefuls, and Cuomo agreed. "It won't be hard to stand out in a crowd of middle-aged white men...