There can't be many brackets in good shape at this point. ESPN tells us that Obama's is in the top 12% - which means, BTW, that he's at exactly the 88th percentile or they would have reported it differently - and good on him for that.
I don't recall sports journalists being interested in Nixon's opinion, and he knew a lot of baseball and football. Or Gerald Ford's, who played football for Michigan. Or Dutch Reagan, who had been a baseball announcer. Or Bush 41, who played 3B for Yale, or Bush 43 who had owned a baseball team (and whose believing Sosa was on the downside of his career looks less laughable now that the steroid info has come out).
In 2009, they even went back and asked ex-President Clinton for a bracket. He didn't do too badly, as I remember.