I hear he's a golfer with the highest paying sponsors in almost all of sports. For the sake of his sponsors, he can't afford to belong to either party. By the time Tiger is 47, he will only be playing the 4 Majors and spending the rest of his time hiding from the public and reporters. The last thing he will ever consider is running for any public office.
It's another case of "who cares what he stands for, he's got star power".