Chances for a tie in the Electoral College.

Based on last night's debate, I believe that today is the closest this race will be—unless the third debate or some unpredictable event fundamentally changes the dynamics. This belief, along with some speculation from around the web about the possibility of a tie in the Electoral College, has prompted me to calculate exactly how much we should worry about a tie between Obama and Romney.

The election currently has nine swing states:

1. IA - Iowa
2. NV - Nevada
3. OH - Ohio
4. WI - Wisconsin
5. NH - New Hampshire
6. CO - Colorado
7. VA - Virginia
8. FL - Florida
9. NC - North Carolina

I list these states in the order that they are likely to go to Obama. For example, Iowa is more likely to go to Obama than Nevada, and Nevada is more likely than Ohio, etc.

Having nine swing states means that there are exactly 512 different scenarios for the election, most of them highly improbable. An example of an exceptionally improbable scenario is one wherein Obama wins North Carolina, Florida, and Virginia while Romney wins the rest of the swing states (1 through 6).

Of the 512 scenarios, exactly five will result in ties. In order from most to least likely, these scenarios are where (from the swing states) Obama wins only:

1. NH, VA, CO, IA
2. NH, WI, OH
3. NH, VA, CO, NV
4. VA, CO, WI
5. NH, VA, NC

So only 5 of 512 scenarios result in a tie. That's less than 1% of the scenarios. Note however that these are very unlikely scenarios. Why are they unlikely? Take the most likely tie scenario as an example. In this scenario, Obama would have to win Virginia (VA), where he is currently trailing, but lose Nevada (NV), where he currently has a nearly sure chance of winning.

Because these scenarios are unlikely, the chance of a tie is much less than 1%. In fact, the chance for a tie is 50 times less than 1% (or 0.02%). Put another way, that is only a 1 in 5000 chance of a tie in this election as it currently stands.

Chances for Victory Update

Here are the Chances for Victory if the election were held on 10/18/12:

• Obama - 98.6% (290 Electoral College votes most likely)
• Romney - 1.4%
• Tie - 0.02%