Instead of beginning with analysis, let's begin with some sad facts; When Kentucky Representative Ben Chandler endorsed Barack Obama, over 500 phone calls flooded his office, the vast majority of them using the word "nigger."
Chandler's aides (who were white) went home shaken, crying, in utter disbelief. They didn't think racism still existed.
If you look at it a different way, the reaction of Chandler's aides might be taken as encouraging.
And if you look at it in yet another, clearer, way it's not necessarily indicative of any fact other than there are a small percentage of miscreants in every place where people live:
Montgomery County, the congressional district of Ben Chandler had a population of 22,500 people eight years ago.
If we assume the population has remained static since 2000, and 90% of the callers used the n-word, and 100% of these callers are actually residents of Montgomery, we are left with 2% of the population of Montgomery County being bigoted miscreants. That's 2% too much, but hardly indicative of a torrent of racism in Montgomery County, let alone the state of Kentucky.
It's understandable that Chandler's aides were upset by the bigoted calls, but they are pretty naive if they think racism no longer exists.
I feel pretty certain that endorsers of Hillary Clinton receive foul sexist messages from a small percentage of miscreants in their areas as well, and I have already seen a small percentage of A2K posters write some outrageously malicious things about McCain.
I happen to think that if Obama wins the nomination it will be a very close race and a small percentage of people who would never leave such offensive messages but will also not vote for a black man, may decide the contest (at the very least there will be no shortage of people explaining his defeat in this way), but I base this on nothing more than a sense of things, and could easily be wrong. Certainly the Chandler incident isn't even anecdotal evidence for my sense of things.