The black curves indicate the median of the electoral vote estimator (top graph) and the Popular Vote Meta-Margin (bottom). For the EV estimator, the gray shaded region indicates the calculated 95% confidence interval. This confidence interval includes sampling error, variation in biases among pollsters, and changes in opinion during the period when the polls were taken. Because pollster biases tend to cancel one another on average, the true 95% confidence interval is smaller, typically less than +/-10 EV.
This plot now contains short-term predictions for the November 6th election. The calculation is explained here. The red zone is a “strike zone” showing the 68% confidence interval of probable outcomes, based on random movement from today’s polls.
The yellow zone is a “watch zone” that shows a combination of the 95% random-movement confidence interval and the 95% gray-zone confidence interval. The November outcome is nearly certain to be within this range.
Notable dates in 2012:
April 25 – Republican National Committee declares Romney the presumptive nominee.
July 12 – Bain Capital / Romney tax attacks begin.
August 11 – Paul Ryan added as GOP VP nominee.
August 27-30 – Republican National Convention.
September 3-6 – Democratic National Convention.
September 17 – Romney “47%” speech emerges.
October 3 – First Obama-Romney debate.
October 11 – Biden-Ryan VP debate. fun!!
October 16 – Second Obama-Romney debate.
October 22 – Third and final Obama-Romney debate.
Notable dates in 2008:
June 7 – Hillary Clinton withdraws from race.
August 1 – McCain campaign releases “Celebrity” ad.
August 25 – First day of Democratic National Convention.
September 3 – Sarah Palin speech at Republican National Convention.
September 11-12 – Sarah Palin on ABC with Charles Gibson; John McCain on “The View.”
September 26 – First Obama-McCain debate.
October 7 – Second Obama-McCain debate.
October 15 -Third and final Obama-McCain debate.