You do realize that a pollster can have a candidate ahead in a poll, and they can ALSO be right if the vote doesn't turn out that way...right? It's called margin of error, and every poll has that factored in, to account for variations for what can actually happen. Hillary was within this margin of error for most of the general election campaign, nationwide, and in the swing states as well.
So if the pollsters said Hillary would win Michigan by, say, 51%-49% and the MoE was +/-3%, then that meant she might get actual votes as high as 54%....OR it could instead be as low as 48%. Because 51% (predicted vote) +3% (MoE) = 54, and 51-3=48.
And guess what? That's exactly what happened. She got votes within the margin of error in four pivotal states, but on the low side, rather than the high.
The next time you see a poll, look for the MoE and realise that an election is only a shoo-in (not shoe-in) if a candidate polls HIGHER than the MoE. Reputable pollsters will have an MoE no greater than +/-3%, so the candidate needs to poll at 53% or over to qualify as a shoo-in. Hilary didn't poll that high in the closing weeks where she needed it.
Ergo, the pollsters got it right.
QED
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