During the debate Wednesday night, President Obama repeatedly claimed Governor Romney's tax plan arithmetic did not add up. But Wednesday, the author of the study Obama relied on admitted Romney's plan could add up using different assumptions.

William G. Gale of the Tax Policy Center is one of the authors of a study which claims Romney's math does not add up. TPC's study claims the Romney plan would shift $86 billion in taxes from the well-off to the middle class. However, this claim relies on certain assumptions, most importantly that cutting tax rates will result in zero additional growth. However, if scored dynamically, "economic growth could fill $53 billion of that $86 billion hole."

That still leaves a gap, but if Romney's plan were also to eliminate exemptions on state and local bonds and life insurance policies, that could raise an additional $45 billion. In other words, it is possible that Romney's plan could actually lower top rates and, by eliminating exemptions and prompting new growth, raise more revenue.

It's significant not just that the math can work but that the author of the study claiming it did not is now admitting, "Under those assumptions and policies it would be revenue neutral." Will Team Obama acknowledge the admission that the math can add up, or will we continue to hear the same objection to Romney's tax plan as if it hadn't happened?