The contours of the electoral map might seem disorienting to those accustomed to the old red-blue divide of the last decade. A bevy of states haven’t returned to their Bush-era patterns—instead, they've moved in opposite directions. Traditionally Republican North Carolina remains doggedly competitive, and Romney isn’t even contesting New Mexico. At the same time, Obama is well beneath 50 percent in states that he carried by 10 percent or more in 2008, like Iowa, Michigan, and Wisconsin. But beneath the chaos, there is a discernible organizing principle: Obama has fallen furthest in the states where he accrued the most white and particularly white working class support in 2008.
State and national polls have long shown that Obama’s already tepid support among white voters without a college degree has collapsed. At the same time, the “newer” elements of the Democratic coalition—college educated and non-white voters—have continued to offer elevated levels of support to the president. And predictably, the imbalanced collapse of Obama’s once broad coalition has rejiggered the electoral map.
This becomes clear when you compare the current RealClearPolitics averages in the 12 battleground states (defined by NBC/WSJ and CNN) and the percentage of voters who were working class Obama supporters in 2008.
The correlation is pretty clear, but keep in mind that these numbers are driven by relatively few data points. Changing just a couple of the polls can make or break the relationship: Simply excluding the recent WAA poll in Virginia, for instance, moves that state directly over the best-fit line. I'd also note that there is a similar correlation with white voters, except that the slope of the best-fit line is not nearly as steep, since college educated white voters haven't moved as decisively against Obama. But overall, it's a convincing explanation of recent shifts in the electoral map.
To be sure, this might not hold until Election Day. If Obama reclaims some of the white working class vote, states like Michigan, Wisconsin, and Iowa would probably move “up” the chart. But for now, the imbalanced collapse of Obama’s coalition has redefined the electoral map, leaving Obama embattled in white working class Midwestern states but relatively well-positioned in the diverse “new coalition" states of the Mid-Atlantic and Southwest.
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