Citizen Forecasts of the 2008 U.S. Presidential Election

We analyze individual probabilistic predictions of state outcomes in the 2008 U.S. presidential election. Employing an original survey of more than 19,000 respondents, we find that partisans gave higher probabilities to their favored candidates, but this bias was reduced by education, numerical sophistication, and the level of Obama support in their home states. In aggregate, we show that individual biases balance out, and the group's predictions were highly accurate, outperforming both Intrade (a prediction market) and fivethirtyeight.com (a poll-based forecast). The implication is that electoral forecasters can often do better asking individuals who they think will win rather than who they want to win.