For myself, I am confident and think it is proven that Barack Obama can win non-African American votes, at least outside of the Deep South. Since Democrats never win in the Deep South anyway, it is not an issue in my opinion for Obama's electability.
That said, while South Carolina will be a big win for Obama tonight, its Democratic primary demographics are very different than the rest of the country and I suspect it will have little impact on the primaries to come. But it will be great to get past this South Carolina primary, which has not been good for the campaign.
Update [2008-1-26 9:28:10 by Big Tent Democrat]: The Media is truly unbelievable in its hatred of the Clintons. Craig Crawford calls them out wonderfully this morning on MSNBC. And Joe Scarborough says something that is remarkable - that Barack Obama's drop with white voters is due to "Clinton race baiting." But this simply ignores the fact that Obama made a much more explicit appeal to African Americans for months prior to that, indeed in response to the bogus "is he black enough concerns. Moreover, the polling simply does not bear out Scarborough's analysis. Consider Obama's percentage of the white vote in South Carolina as polled by Mason Dixon.
In a December 3-6 poll, Obama got 10% of the white vote (37% of the A-A vote.)
In a January 14-16 poll, Obama got 20% of the white vote (56% of the A-A vote.)
In a January 22-23 poll, Obama got 10% of the white vote (59% of the A-A vote.)
Obama has NEVER gotten the white vote in South Carolina. Never. And indeed, what has happened is that Obama has completely solidified the African American vote.
Of course that is one poll. In the Survey USA poll, Obama's white support has remained steady at 21% for the past 10 days.
In the Zogby poll, Obama's white support has GONE UP 1 point this week, from 18% to 19%.
In the Rassmussen poll, Obama's white support has remained EXACTLY the same this week, at 21%.
The fact is the demographics of support for the candidates has remained VIRTUALLY unchanged this entire month! If the race card was played THIS week, then it failed miserably. Nothing has changed in this race at all.
These figures are important as the Media is sure to try an inject the racebaiting narrative tonight. Keep these figures in mind.