Polls may be making voters worse at predicting elections

Something changed when Obama and Romney faced off. In earlier elections, the percentages predicting a “close race” or a “win by quite a bit” varied predictably with the closeness of the race.

In 2012, however, voters were far more confident — with large percentages believing that either Obama or Romney would win by quite a bit. You can see this in the graphs below, where the 2012 data points sit far away from the others.

These confident 2012 predictions are particularly striking given that polls showed a very narrow Obama lead.