While much of what will happen on Election Day is now unknowable, we can predict with certainty that President Obama won't win a majority of the white vote.
No news there. No Democratic presidential candidate, after all, has received the support of most white voters since President Lyndon Johnson's 1964 historic rout of Sen. Barry Goldwater of Arizona.
Still, four years ago, Obama did manage to get a very respectable 43 percent of white voters to choose him over Goldwater's Senate successor from Arizona, Sen. John McCain.
That was then.
As Election Day 2012 nears, Obama appears unlikely to come anywhere near to attracting the percentage of overall white voters he did four years ago.
But that may not matter because of growth in voter groups much more inclined to back the nation's first black president, members of minority groups, especially African-Americans and Latinos, who can counter Obama's losses with many white voters, especially those defined as working class.
How bad are Obama's prospects with white voters? A recent Washington Post-ABC News poll put Obama's support among white voters at 38 percent, dangerous territory for a president seeking re-election. The same poll placed Republican Mitt Romney's support from white voters at 59 percent.
The Washington Post reported that was the lowest level of support for a Democratic presidential candidate since 1988, when Michael Dukakis received 40 percent of the white vote against then-Vice President George H.W. Bush. (The Roper Center indicates Bill Clinton came in slightly lower than that in 1992, at 39 percent of the white vote in a three-way race featuring Bush and Ross Perot.)
In 2008, Obama lost white working-class voters to McCain by 18 points. He's not the only Democrat to fare poorly with these voters. In the 2010 congressional midterm election, which found Democrats losing control of the House, Democrats lost the white working-class vote to Republicans by 30 points.
There appear to be exceptions, however, as in all-important Ohio. A recent Quinnipiac University poll showed Obama trailing Romney among white voters without a college degree there by only 4 percentage points — Romney, 49 percent, Obama 45 percent.
That helps explain why in a number of Ohio polls, Obama has a small lead over Romney.
For Romney to win Ohio, he would need to drive down Obama's support with white voters, said Peter Brown, assistant director of the university's polling institute, who was quoted in a news release:
"President Obama won 46 percent of the white vote in Ohio in 2008 when he carried the state by five points. Romney probably needs to hold Mr. Obama to less than 40 percent of the white vote if he is to win Ohio, and he has a ways to go at this point."
Even as Obama's support from white voters has slipped, those losses have been offset, more or less, by other voters, as minorities, who identify strongly with the Democratic Party, become a larger part of the population of eligible voters.
"It depends on what you're putting the emphasis on, right?' said Ruy Teixeira, one of Washington's better-known political demographers, in an interview. Teixeira has long buoyed Democrats with his predictions that the nation's changing demographics favor Democrats. "Is it more interesting that Obama's going to do worse among whites or is it more interesting that Obama is going to hold all of his minority support from 2008 and then some, which is actually quite remarkable?"
In April, and in a report called "The Path to 270," Teixeira argued that Obama's support from minority voters could result in the president's winning re-election even if Romney outperforms the numbers McCain got nationally among white voters.
As Teixeira explained at an April panel discussion at the Bipartisan Policy Center in Washington, Obama could still win even if he does as badly with white voters as the 2010 congressional Democrats (again, they lost white working-class voters by 30 points. They lost college-educated whites by 19 points).
And Obama could still win if he does as badly as Sen. John Kerry in 2004 against President George W. Bush. The Democratic presidential nominee that election cycle lost white working-class and college-educated voters by 23 percent and 11 percent respectively.
Teixeira told the audience at the April event: "Obama could do as badly as John Kerry did, but the country has changed enough in the last eight years, he could still pull out the election if he got 75 percent of the minority vote."
And that 75 percent is a somewhat conservative figure. Obama's support from nonwhites is hovering above 80 percent, according to polling from the Washington Post-ABC News.
A quick look at population changes in battleground states illustrates why the Obama campaign has reason for confidence despite the challenges of being an incumbent president during a period of relatively high joblessness.
Here's the growth of the nonwhite eligible voter populations in battleground states between November 2008 and May 2012, according to William Frey of the Brookings Institution, another of Washington's better-known demographers: Nevada, up 9 percent; North Carolina, up 4 percent; Florida, up 4 percent, and Colorado, up 3 percent. The white share of the eligible voting population declined in all those states.
Even more important than the percentages of whites, blacks and Latinos in the electorate is who actually turns out to vote. In 2008, Obama benefited from lower intensity levels among white Republican voters who didn't turn out for McCain in the necessary numbers.
All indications are that 2012 should be different. Republicans are demonstrating significantly more enthusiasm than in 2008, buoyed by the thought of ousting Obama and placing Romney in the White House.
Frey ran some computer simulations of what could happen on Election Day. One scenario mimicked the higher turnout of white voters in the 2004 general election and the enthusiastic turnout of nonwhite voters in 2008 for Obama. Obama won the election, but not by much.
"Demographics, not just meaning the underlying demographics, of course, but the eligible voter population and the turnout, which is important, that's still kind of a question mark," for Election Day 2012, Frey said. "We can do all these simulations, but we really don't know who's going to turn out and how big those turnouts are going to be."
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