There are some perfectly persuasive right-wing arguments for getting behind Mitt Romney: He's the most electable choice remaining in the field, and he may be a con man, but, once elected, he'll be forced to honor the promises he's made to conservatives.
On the other hand, you have some conservatives who realize that Romney offers the best ticket to defeat Obama, but are struggling to process the cognitive dissonance involved in supporting a figure with such a moderate past. So they have engaged in all kinds of hilarious efforts to explain away policies they would normally condemn as socialist tyranny. Here's Ann Coulter, a Romney endorser, defending his health care plan:
Romney pushed the conservative alternative to national health care that, had it been adopted in the 49 other states, would have killed Obamacare in the crib by solving the health insurance problem at the state level.
True! If we had Romneycare in every state, then taking the exact same plan and reproducing it at the national level would be unnecessary. So how about if we compromise and replace the Affordable Care Act with 50 state-level versions of the same thing? Conservatives get to repeal the hated Obamacare, liberals get ... well, I don't want to jinx the deal by saying what we'd get. Let's just go with it.