What is particularly interesting about Obama's response is that he is implicitly suggesting that the electorate is latently racist and that when McCain, et. al. make ads like this they are in fact stirring what should remain latent. In other words, Obama is not insulting McCain's campaign, but he is actually complementing it! He is saying, "You sneaky bastards, you're manipulating the dumb and malleable unwashed masses that should legitimately be mine." Obama is insulting the electorate and employing that insult to shame and bully them into voting for him. If I may use a Platonic allusion, Obama is procuring the tactic, "Mandatory diversity training writ large." That's not "hope." That's fear; fear of shame, fear of being called a racist, fear of others thinking you may not like the black guy. So, when Obama says he wants "change," he is talking about you. You need to change, to become more "enlightened," unlike your Reagan Democrat parents who were probably racists. Obama does not want to dialogue with you, since to do so would imply that you may actually have a rationally defensible position that has a point. He wants to shepherd you through the transition out of your benighted red state moronic worldview. In Obama's universe, it's okay to talk down to people who are in fact beneath you. You are beneath him. Get with the program or he'll call you a racist.
There's a pattern emerging: Obama seems to instinctively resort at every turn to his one-size-fits-all explanation for why certain people and groups in our society would disagree with him: they are fundamentally irrational and need to be taught by the enlightened like him. From his comments about "clinging to guns and religion" to his prophesy that his opponents will say "he has a funny name" and "he is black" to the ease by which he appeals to "divisiveness" to account for the beliefs of the citizens of California who want to protect their understanding of marriage by means of amendment, Obama is suggesting that opposition to his candidacy and the ideas he holds dear cannot in principle arise from legitimate and serious disagreement by well-meaning fellow citizens.
The only audacity is calling this "hope."