"There is nothing inherent in the economics of Massachusetts that should be singled out," said Gruber. "There's only two things that should be singled out in Massachusetts- one is we did have widespread acceptance of the mandate, which may not be true elsewhere. But the biggest thing that Romney's not talking about is in Massachusetts the federal government paid for about half of our plan. We didn't pay for it all on our own."
Gruber says that this makes it harder to argue that state's can easily adopt plans similar to the one in Massachusetts. The economic impact on a similar plan not aided by the federal government can't be accurately compared to the Bay State.
The mandate has been a big part of the reforms success, says Gruber.
"The mandate I think played a key role," Gruber said. "Once the mandate took effect you saw a bunch of healthy people coming in who weren't coming in beforehand. I think the mandate's been a critical element of that."
The Supreme Court is expected to rule on the Affordable Care Act, also known as Obamacare, by the end of the month.