I hate to say this but the voters will not want to take a chance with a woman and a black. They will want at least one white dude on the ticket just in case the Shiite hits the fan.
Being both black and a female, I agree with your position. Voters in this country are not about to vote for a black guy and a woman 1) in the middle of a war, 2) together, without either a black or a woman having already been president.