With the 2012 elections less than a year away, Republicans’ struggle over health care could be a political liability. Democrats will blast them for breaking a promise.

It could be even more of a problem after the election. If the GOP can repeal the law, it would reopen the ugliest political fight of the past five years.

But the GOP wouldn’t have a plan to win it.

“If Republicans aren’t talking about how they would replace Obamacare,” said Michael Cannon, the libertarian Cato Institute’s director of health policy studies, “there are two good reasons for that.”

“The first one is: They’re winning the argument. Why would they change the subject?” Cannon said, meaning that Republicans have won support by focusing only on the “repeal” part of their promise. “The second one is: Their current proposals [for replacement] aren’t ready for prime time.”