My computer screen unexpectedly died the other day, requiring a trip by the computer to the computer hospital for an operation to replace the screen. The operation was a success and the computer was returned to my office this morning. As my model was on this computer, I was forced to wait patiently for the computer to come home so that I could update the model.
While the computer was ill, the character of the presidential race naturally changed. The Republican post-convention bounce has turned out to be real and the swing of the pendulum has put McCain out in front by 2.2 percentage points:
More importantly, McCain's modest margin translates into a near-comfortable margin in the Electoral College:
The updated electoral map shows that the south and interior west are now a solid bloc for McCain:
My model is showing McCain in the lead in Iowa and New Hampshire. This is likely to be somewhat controversial since Obama is widely thought to be ahead in both states by a modest, but reasonable, margin. However, no post-convention poll has been taken in Iowa so we have no direct measurement of any kind yet from that state. A poll showing Obama with a six point lead in New Hampshire was released after the conventions, but that is just a single poll and the error in one poll could easily be greater than the six point margin. My model's estimations for these two states and for the other seven states where the margin is four percentage points or less is shown below:
McCain's Iowa lead is just a sliver and is hardly comforting in Colorado, Missouri, New Mexico and Ohio. Ominously for Obama, Oregon and Pennsylvania have crept into this list of swing states and Wisconsin is simply too close for comfort. If any of these states slip from Obama's grasp, the election is effectively over.
I've compared the results of my model with the model on the website fivethirtyeight.com. Although this model shows McCain with a 2.4 percentage point lead (0.2 percentage points greater than my model), their state-by-state figures show McCain with a slender 274-264 vote lead in the Electoral College.
I'll have a bit more to comment on their model and this map tomorrow.