If you really want to analyse US elections, look through the elections on wiki and google a few links. That's what I've done, and I think Obama will NOT win, though he should win. Should, however does not mean I would like him to win.
Basically, the republican party is so weak after two terms of Bush as long as the democrats can put up any average presidential potential who is still breathing by november, they would win. However the dems took a huge risk and put forward a black man (and a woman), so they immediately lost 12 of the 13 southern states, and possibly reduced their chances in Florida too. I'm not saying everyone in the southern states is a racist and sexist, but I am saying a black liberal lawyer from the North running up against an old white war veteran is going to find it hard pulling southern votes. Historically in order for the democrats to win US elections you need the southern states: Kennedy/Johnson won because Johnson was governor of Texas; Carter won because he representated the new integrated south with the support of southern whites he carried most of the southern states, Carter was governor of Georgia; Clinton was governor of Arkansas. Compare that with Obama? Also, young people from minority groups really striving for reforms like Kennedy (Catholic) and Obama (Black) will probably be assassinated anyway.
Obama should win because he is the progress candidate running for change and reforms, so at least he is trying to do something about the current mess. But I really don't care whichever side wins, because it will make no difference for US foreign policy.