Despite his Michigan and Arizona primary wins last night, Mitt Romney continues his trend of underperforming among working- and middle-class voters. In Michigan, according to exit polls, Rick Santorum topped Romney in all categories of voters earning less than $ 100,000, while Romney won voters earning $ 100,000 or more, reaching 55 percent of the vote among people making $ 200,000 or more. In Arizona, where Romney won a substantial victory, he carried every income category. But his performance improved steadily as incomes increased: He took 37 percent of voters earning under $ 30,000 and 67 percent of those earning $ 200,000 or more.
If Romney is the ultimate Republican nominee, that’s a worrisome trend for a party that depends not just on winning white working-class voters but on winning them by a large margin. These being Republican primaries, the voters are overwhelmingly white—89 percent in Arizona and 92 percent in Michigan, compared with general populations that are 73 percent white in Arizona and 79 percent in Michigan. But, of course, Republicans depend most on white voters of whatever income level to win general elections—within that, white working-class voters become a crucial swing category. Having a nominee who’s shown, in primary after primary, that he can’t appeal to those voters, would not be good news for Republicans.