Notwithstanding these modest fluctuations, the two new surveys reinforce the message of the four other national polls National Journal examined earlier this week. All of them show Obama largely holding two pillars of the modern Democratic coalition-minority voters and college-educated white women. But all show him facing significant erosion among blue-collar white men, and in most surveys he's also confronting at least some loss among college-plus white men and non-college white women. It will be difficult for Obama to ever establish a comfortable advantage while he faces such entrenched resistance from so much of the white electorate. The mirror image challenge for Romney is that if Obama holds support from minorities and well-educated white women equal to (or even above) his 2008 levels, Romney must win almost two-thirds of all other whites to fashion an overall national majority.
It's worth remembering that when Republicans increased their showing among whites to a record 60 percent in the 2010 House elections, they advanced not only with the portions of the white electorate historically most disposed toward them, but also drove down the Democratic support among college white women to 43 percent, according to exit polls. For that matter, in that election they also reduced the Democratic share of the non-white vote to 73 percent. If Romney can't make at least some gains among those two blocs in 2012, his math grows much more daunting.
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