For those Democrats who have been puzzling over the inability of the Obama campaign to get more traction with white male voters, Brian Montopoli has an excellent post up at CBS News Politics, with the somewhat misleading title, “Will White Men Sink Obama?”
The title is misleading because Montopoli makes it clear that Obama can win; it’s more about the reasons behind the segmentation of the white male vote at this political moment. Montopoli sheds light on the challenge facing Democrats with this still-influential constituency and provides some insightful observations, including:

…While women outvoted men by about 10 million votes in the 2008 presidential election, men still made up 48 percent of the electorate. And white men alone made up more than one third of the electorate – 36 percent – according to national exit polls.
It’s true that whites are slowly shrinking as a portion of the electorate as blacks, Hispanics and Asians grow in influence, which is why you don’t see many news stories about them as a voting bloc. But they still pack a powerful electoral punch. White men, in fact, are providing the biggest drag on the president of any voting bloc as he tries to win another four years in the Oval Office. Even if the president gets his expected 80 percent support from minority voters, he is unlikely to win the election if he can’t win more than one in three white men. And he might not.
A Washington Post/ABC News poll released this week found that white men support Romney over Mr. Obama 65 percent to 32 percent – a 2-to-1 margin. That suggests the president is doing worse among white men then he did in 2008, when exit polls showed he lost white men by a 57 percent to 41 percent margin. The poll also found white men moving away from the president: Romney’s 19-point mid-October lead on handling the economy among the group has risen to 35 points today.

Montopoli quotes Progressive Policy Institute President Will Marshall on the problem:

Many white men, and many, in particular, non-college white men, have not seen that the Democratic economic agenda is in their interest…There’s an account from the left that says these voters have been estranged from Democrats on social issues. And there’s some truth to that. But I also think these voters believe the economic policies of Democrats have benefitted somebody else – not them…

But, as Montopoli points out, there is a strong regional influence on the way the white male vote breaks down:

…A survey released last month by the Public Religion Research Institute (PRRI) found that Romney led 48 to 35 percent among whites lacking four-year college degrees who are paid by the hour or the job. Yet while Romney led by 40 points among southern working-class whites, the president actually led by eight points among Midwestern working-class whites. The president’s relative strength among whites in the Midwest is the reason a state like Pennsylvania appears likely to remain blue despite a relatively large white population.

As Marshall puts it in Montopoli’s post, “The sense that he’s doing better with white voters in the Midwest is the firewall for Barack Obama…It’s what’s giving him hope that he can win in the Electoral College even if he potentially loses the popular vote.”
Montopoli adds that Romney is weaker in the more unionized midwest, despite his Michigan roots, as a result of his opposition to the auto bailout and Obama’s relative popularity in the region. With white working-class women, however, the situation is a little more complicated. Moreover, adds Monopoli:

…The PRRI study found that while Romney holds a 2-1 advantage among white working class men, the two candidates were tied among white-working class women. David Paul Kuhn, author of “The Neglected Voter: White Men and the Democratic Dilemma,” reported that Democrats have seen a 25 percent decline in white working-class male support between 1948 and 2004, even as white working-class women held steady.

But the Bush meltdown may have exacerbated the insecurity of white men in particular. “The effect of the 2008 economic collapse has been dubbed a “he-cession” because it disproportionately left men out of work,” adds Montopoli.
Romney, for his part, has been struggling to make inroads with white male working-class voters in the region with repeated references to “the war on coal” and the like. But his campaign seems to be stuck in neutral at the moment.
It does appear that 2012 may be the last election in which the white male vote is a decisive force. As Montopoli concludes, “The silver lining in all this for Democrats: The impact of their disadvantage among white men looks likely to diminish as time goes on.”