Just remember—he was for the marriage ammendment before he was against it.  Or something like that:

Look at all the candidates who now have the same position on gay marriage: Hillary Clinton, Barack Obama, John McCain, Rudy Giuliani and now Fred Thompson. They all say ... they are against gay marriage.

Mitt Romney, amazingly, is now the ONLY major GOP candidate who supports putting these [activist] judges in their place with a federal marriage amendment.