Why the Polls Are So Often Wrong - Powerline

The big story today, as over the weekend, is the resurgence of Republicans in a number of recent polls. That resurgence has been picked up broadly enough that it is fair to assume it is real. Still, though, we are seeing it through the medium of the polls. There is a more basic issue that clouds the polls' ability to predict what will happen tomorrow, and the ABC/Washington Post poll, one of those showing a Republican comeback, exemplifies the reason why.