Electoral Vote Math: Obama 193, Romney 0 [View all]

[Playinghardball]

As Rolandz notes, Nate Silver has had some steadily encouraging numbers for Obama: his current forecast for Nov. 6, up even from yesterday, is a 73.1% chance of winning, and a healthy 305.5 estimated Electoral Vote total. I decided to drill down a bit to the state level, and discovered a really interesting fact: using the probabilities given for winning each state (or district, in Maine and Nebraska), Obama has 193 ways to get to 270 electoral votes by winning states for which his chances are at least 50%. The number of such routes to 270 for Romney? Zero.

To see why, follow me over the squiggley speed bump.

Along with the overall chances of winning the election, Nate Silver's FiveThirtyEight Blog also computes probabilities for winning each state/district (a combination of polling info, trends, underlying facts relevant to the given state, etc.) One fairly simple thing you can do to get a sense of the race is to assume that, starting with states that each candidate is guarranteed to win, work your way down the probabilities adding electoral votes as you go. So for example, Obama currently is given a 100% chance of winning nine states (go Vermont!) and Maine, district 1, followed by 11 states between 90 and 100%, ending at Pennsylvania with 91%. Assuming Obama will win all of these, we proceed through the next four states, all between 70 and 80%, ending with Ohio at 71% for a total of 275 electoral votes.

Notice that to get to 270, using only Obama's highest probability states, we never had to use a state with lower than 70%. On the other hand, doing the same process for Romney, using only his highest probability states, he has to use states for which he has a less than 50% chance of winning-- in some cases, much less. Put another way, the easiest path to 270 for Romney-- in terms of current probabilities-- runs through three states between 30 and 40%, ending with Ohio, at only a 29% chance of winning. That's gotta hurt.

But wait! There's more...

While Romney has no path to victory using states where his chance of winning is greater than 50%, Obama has not just one but many such paths. I've summarized all of them in the chart below.



http://www.dailykos.com/story/2012/09/01/1126847/-Electoral-Vote-Math-Obama-193-Romney-0