Mitt Romney tries, again, to convince voters that he's authentic.

Romney invoked the principle of federalism, saying that governors have more leeway in many ways than presidents because states are the "Laboratories of Democracy."  But conservatives most likely to buy that argument have trouble with him for other reasons. They don't like that his Massachusetts plan included a mandate to force people to buy insurance. The speech was barely over before Rick Santorum issued a statement decrying "both Romneycare and Obamacare" because they "infringe upon individual freedom." Avik Roy writing in the National Review, said "Mitt Romney just gave a more articulate defense of Obamacare than President Obama ever has." The Wall Street Journal, meanwhile, didn't even wait for the speech, publishing a full-throated attack on Romney and his health care plan on Thursday morning.

All of this would make even the most confident fellow a little halting and nervous. That's what Romney looked like at times as he looked up at his Powerpoint slides from behind the lectern and made tentative jokes. It looked very authentic.

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