The Obama campaign responds:
"Mitt Romney today said that he did indeed ‘go back and look’ at his tax returns and that he never paid less than 13% in taxes in any year over the past decade. Since there is substantial reason to doubt his claims, we have a simple message for him: prove it. Even though he’s invested millions in foreign tax havens, offshore shell corporations, and a Swiss bank account, he’s still asking the American people to trust him. However, given Mitt Romney's secrecy about his returns, coupled with the revelations in just the one return we have seen to date and the inconsistencies between this one return and his other financial disclosures, he has forfeited the right to have us take him just at his word."
And Sen. Reid office responds:
"We'll believe it when we see it. Until Mitt Romney releases his tax returns, Americans will continue to wonder what he's hiding. Romney seems to think he plays by a different set of rules than every other presidential candidate for the last thirty years, all of whom lived up to the standard of transparency set by Mitt Romney's father and released their tax returns."
The ball's still in your court, Willard.