Mitt Romney has had a bad week, and his “maybe” answer regarding his willingness to release tax returns for prior years like his father did many years ago will likely go down as one of those iconic campaign moments that help define a candidate.

It was obvious to me for the past month that this would be a real issue. The tax code has been manipulated for years by lobbyists, and wealthy financiers like Romney get huge breaks, including the indefensible carried interest.

Romney is particularly vulnerable on this issue as he’s proposing to lower tax rates on the wealthy even more. Now he has compounded the problem with his muddled answers.

The ad above was created quickly after his disastrous debate performance. Right now the polls suggest he’ll lose the South Carolina primary to Newt Gingrich.