To hear any Republican tell it, Barack Obama must tear down Mitt Romney because he's got nothing to boast about in his own record.

But strangely, Mitt Romney doesn't run much on what he did in Massachusetts during the only four years he's ever held elective office, instead emphasizing his track record as a turnaround artist during his 15 years at Bain Capital.

Of course, one of his signature accomplishments, providing a universal health care system in Massachusetts, is something that Romney has been close-mouthed about, since the national version which President Obama copied is the number one issue that has rallied Republicans in opposition to the president.

Now after attacking Romney on Bain, the Obama camp is airing a national ad going after Romney's record in Massachusetts.