How to explain this anomaly? A significant number of Obama supporters – 18 percent of them in the exit poll – voted for Republican Walker today, while just 6 percent of Romney’s supporters crossed over to support his Democratic rival, Milwaukee Mayor Tom Barrett. It may be that some Obama supporters thought that the recall was too extreme a remedy or favored Walker’s attack on public-sector unions (which 51 percent of voters in the exit poll supported, against 48 percent who opposed it).

Neither Romney nor Obama is wildly popular within the white working class of the once-industrial Midwest. It’s easy for Obama’s opponents to depict him as culturally alien to those voters, just as it’s easy for Romney’s opponents to depict him as the guy who closed the local plant. But based on today’s exit polling, Obama’s in better shape than Romney, perhaps because the Republican candidate is simply not viewed as caring about the middle class. Asked which candidate would help the middle class more, Wisconsin voters preferred Obama over Romney by an 11-point margin, 47 percent to 36 percent. The president may be an arugula guy, but he was once socked with student loans, just like a normal person. Little about Romney’s life experience, by contrast, comes across as normal.

What the exit poll doesn’t show, of course, is what would happen if Republicans outspend Democrats in November’s presidential contest by the same margin – roughly 3.5-to-1 – that they did in today’s gubernatorial contest. Nonetheless, while today’s election offers precious little for liberals or union advocates to cheer about, it does suggest that the president’s hand, even in the largely white industrial heartland, is stronger than many have thought.