Offering a sneak peak of the 2012 Republican primary, a spokesman for former Massachusetts Gov. Mitt Romney on Thursday defended the sweeping health insurance overhaul that Romney helped enact in Massachusetts in response to criticism from former and possibly future presidential rival Mike Huckabee. “Mitt Romney is proud of what he accomplished for Massachusetts in getting everyone covered,’’ said Romney spokesman Eric Fehrnstrom. “What's important now is to return to the states the power to determine their own health care solutions by repealing Obamacare. A one-size-fits-all plan for the entire nation just doesn't work.''