Today Mitt Romney is arguing that there were attacks from Rick Santorum this week that he didn't get a chance to rebut -- thus in some way explaining his three defeats on Tuesday night. But I see a different pattern. It's not unusual for also-rans to opportunistically pick up a caucus here and there, even when there's a more or less anointed frontrunner. And it's true Romney didn't campaign or spend aggressively in those states. But the frontrunner, already prepping for the incumbent, shouldn't need to go full court press just to stave off resounding defeats at the hands of a palpably second or third tier opponent. It looks more like Mitt Romney -- at least in this cycle -- is a sort of electoral Bubble Boy, unable to exist in the natural political environment without a protective layer of massive SuperPAC spending.
Look at the story in Iowa, South Carolina, Florida and Tuesday's contests. Each tells the same story.