As I wrote in Reason:
Barack Obama has not run as the typical candidate, selling specific policies, a worldview, experience, or executive competence. He has instead sold himself, a glamorous icon onto whom supporters project their hopes and dreams and, in many cases, their own identities. If elected, he will have not a policy mandate but an emotional one: to make Americans feel proud of their country, optimistic about the future, and warmly included, regardless of background, in the American story.
Last night's excellent speech, with its sober tone and appeal to unifying national ideals and experiences, suggests he understands what he was elected to do. Of course, that doesn't mean he can keep it up.