Here's Herman Cain explaining what I think is the heart of his appeal to the right:

The African American radio talk show host said that his own campaign takes the race card off the table.
“It takes it off the table,” he said. “The Obama administration... they selectively played the race card and they selectively played the class warfare card. Whenever someone disagrees with the president, oh it must be race and I have some seen people do this -- which is just ridiculous.”

What is the evidence that the Obama administration plays the race card any time somebody disagrees with it? Where's the evidence that Obama or his administration has ever accused its critics of racial motivation? I can think of one stray line from during the campaign, when Obama went off script and characterized commercials against him as focusing on the fact that he "doesn't look like all those other presidents on the dollar bills," a remark for which Obama was widely pummeled, quickly backpedaled from and abandoned.

Huge numbers of conservatives, though, genuinely believe that Obama has used his race as a shield, intimidating critics into silence or undue deference. Thus the appeal of Cain, the man who can neutralize the only thing Obama has going for him.