[swader999]

Agree. Polls are a bad metric to rely on. Only 2% of those asked respond. Impossible to get a statistical sample with that. People are bad at predicting their future behavior. They are dishonest, they don't know or just don't want to tell you. There's a huge class divide right now. The bigger the class divide the worse polls are historically. And we know they are wrong this time around. None of the early voting margins predicted have held close. Better predictors are Google trends, rally participation, and voter registrations.

[disgruntledphd2]

Sure, these are all concerns. However, as long as they are not systematic errors for or against one candidate, they end up not mattering very much.

Andrew Gelman (the author of this post) has also done a bunch of work on how different parties supporters become more/less likely to respond to polls based on what the current results are, which has been incorporated into the newer forecasts.