It’s been part of Mitt Romney’s and the GOP’s line of attack on President Obama’s time in the White House: Obamacare is already costing Americans and should be repealed.

Romney just this week suggested that the Affordable Care Act, which the Supreme Court is expected to rule on as soon as Monday, is prompting small businesses to cut hiring, a potential economic killer. “It is having an impact on middle income families that want to have good jobs,” said Romney.

But on Wednesday, one of Washington’s arbiters of the law said Obamacare isn’t an economic drag. “We don’t think that the health care law is having a significant impact on the economy today,” said Doug Elmendorf, director of the Congressional Budget Office.

“There are a lot of pieces of the law, some unfolding today, and expectations that future changes in policy can matter, but we don’t think it is having a significant impact on the economy today,” he added.

That was much better news than the blunt-speaking Elmendorf had for Congress’ bungling of the budget, taxes and pending sequestration that could rob $500 billion from the Pentagon if a deal on spending and the Bush tax cuts isn’t agreed to by the end of the year.

“What I worry about most is that our political system needs to come to grips with this fundamental choice about whether we going to let taxes rise relative to what we are used to in the past, or cut spending on the big popular entitlement programs or some combination. That’s a difficult trade off,” he said at a media breakfast hosted by the Christian Science Monitor. “It’s made more difficult, I think, by a lack of understanding on the part of many Americans about where their federal dollars go,” he added.