Didn't Nate Silver say that was the most likely split? There was a post about it on HN for like the past 2 days.

Edit: The confusion is probably that Silver was reporting the average electoral split as his prediction, when the mode is more important in what you're talking about. His average was almost never a number that was actually possible, since he was quoting them to the nearest 1/10th of a vote, so its kind of unfair to punish him for not getting it exactly right.