Nate Silver on looks:

[W]hen Obama does the things that a President might do -- going abroad and meeting with foreign leaders and military commanders, or delivering a speech to an international audience -- it no longer becomes difficult to contemplate the idea of him as President. We might not know exactly what would happen if Obama were elected. But we have some idea what an Obama Presidency would look and feel like. We might not agree with everything that Obama has to say. But we can imagine him standing in front of the country -- as President -- and saying it. The fear of Obama's 'otherness' is reduced. One may be skeptical of an Obama presidency, but [one] probably isn't scared of it.