Confidence of Victory prediction for the South Carolina-01 special House seat.

Unlike the races last November, the special race for the South Carolina 1st District seat is not being polled to within an inch of its life. The only company keeping track is Public Policy Polling (PPP), a Democratic polling company that does automated polls often called robo-polls. After some early polls that had Democratic candidate Elizabeth Colbert-Busch ahead, the latest poll released today has a 1% lead for former governor Mark Sanford at 47% to 46%, with another 4% favoring the Green candidate Eugene Platt and the rest undecided. The sample was taken this weekend for 1,239 likely voters.

The system I use, which I call Confidence of Victory, takes the two leading vote getters in a situation like this and calculates the probability that a lead in this poll will translate into a victory in the election. With this lead and this size of a sample, Sanford has a 64% Confidence of Victory and Colbert-Busch's probability is at 36%. My system assumes a 0% chance for the Green candidate so far behind.

I would like more polling data from more companies, but if only one company reports data, it would be hard to top PPP. In their polls of the electoral college and Senate races from the last week of the general election, they went a perfect 33-0 in predicting winners. We will see tomorrow night how my prediction from this one polls fares and I will report back.