As we've never had a woman president, I don't see anything wrong with a voter deciding to give a woman a chance, simply because we've never done it. Hillary's the woman running, and she has a real shot at winning. If a voter thinks Clinton's and Obama's good and bad policy positions are a wash, I don't see anything wrong with that voter preferring Clinton over Obama because he thinks it's time for a woman to be prez. Same thing about Obama and race.
I'm not quite sure what you're referring to in your first statement, cj. I'm not aware that Obama has gotten any free pass.