Since mid-February most states have drifted slowly toward their initial favorite. Even in early May, many states provided the whiff of promise with a 10 or even 20 percent likelihood of being picked off by the trailing candidate. This has not been a year of surprises. As you run the map from May 1 to October 23, you see states fleeing to the safe, dark colors until only a handful of the true swing states remain standing.
By shifting the shading cutoff at the bottom of the map, you can see how sparse those swing states really are. If you define a swing state as one where the underdog candidate has at least a 35 percent chance of winning, only three states make the cut: Colorado and Virginia, which both lean slightly toward Romney, and New Hampshire, which is 63.9 percent likely to go to Obama. Iowa and Ohio join the fun right below that 65 percent point for Obama.
We will update this map regularly over the next two weeks. One thing we know for certain: The light colors will get sparser and sparser as we approach the day of judgment.