Nate Silver:

Well, we have Obama with a 77 percent chance on the site. My personal prediction would be pretty close to that. Those would be the odds I would be willing to establish at a betting line. In the book I say we should try to make probabilistic forecasts and almost look at ourselves as being sort of bookmakers or gamblers. That’s the closest compromise between the uncertainties in the real world and our ability to perceive them. That’s as well as you can do. At this point it does look like we have a clear favorite, but we could be surprised.