Andrew Sullivan and others sneer at Romney's debate proposal that illegal immigration can be resolved through "self-deporting," but the idea is sound. If enforcing regulations on employers means that illegal aliens face worse economic conditions by their presence in the United States than they would by staying south of the border, there won't be illegal aliens because they won't come in the first place, and leave if they're already here. There's certainly evidence that the recession reduced illegal immigration over the last four years; there's no reason to think that illegal aliens don't respond to economic incentives. (Indeed, the main problem with amnesty proposals is that they encourage future illegal immigration in the hopes that they'll receive the next generation's amnesty.) Federal policy can make a big difference here. The Obama administration's hypocritical upside-down-federalism lawsuits against Arizona and Alabama for attempting to reduce the costs of illegal immigration, refusal to enforce deportation law, and attempts to encourage voting fraud by suing states that dare to require ID at the polls are all examples of the policy going 180 degrees the wrong way.
Of course, Romney discussing the issue in jargon that even pundits don't understand and the fact that the political discourse is so debased that ignorant pundits feel it appropriate to use snark in response are two obstacles that he faces in the road to the White House.