But they could not predict correctly who would win.
anti-US Kalifornia skews it too much.
The Popular Vote polls were not trying to predict who would win the Electoral Vote - however, there is a 91% historical correlation between the winner of the Popular Vote and the winner of the Electoral Vote.
Almost all the Electoral Vote polls predicted Clinton would win, or too close to call.
However, since Trump won Wisconsin and Pennsylvania by a total of 95,000 votes, I assume almost all the Electoral Vote polls were within the margin of error, too.