Below is the latest Electoral Map from CNN. It is based on multiple polls taken in each state and is updated daily with the latest results. According to this map, there are 99 votes “up-for-grabs” — Obama needs 20 of them, whereas John McCain needs 79. Using straight math, and assuming a 50% chance that either candidate will get those votes (this does not take into consideration that votes are awarded in “clumps” based on state), Obama has a 80% chance of winning, while McCain has a 20% chance.
I will update this map and the odds every few days (I should note, this is not a prediction of the margin of victory, it is simply a prediction of who will win).