Jay Cost argues that Romney’s attack ads might have made it difficult for him to win over voters--supporters, especially, of Huckabee--who were otherwise persuadable. Romney might have had the effect of driving down Huckabee’s support, but leaving others to reap the benefit of the defections. And he might also have made it more difficult for Huckabee supporters--having, perhaps reluctantly, concluded that there wasn’t any hope for the man from Hope--to transfer their allegiances to him.

All of this is to say that campaigns matter and that issue positioning isn’t everything.