The networks have called it for Hillary and I think after Florida in 2000 they're not going to make that mistake again, so obviously our polls were wrong.
First off, please do not call us or e-mail us and tell us we suck! We are well aware, and it does not feel good.
It's pretty easy, based on the exit polls, to see where we went wrong. We had the black vote at 18% when it turned out to be 14-15%, and we had the under 45 vote at 41% when it turned out to be 31%.
I reweighted the results from our final Pennsylvania poll to those figures for race and age, and the result of our poll was flipped- Hillary leading 49-46. Assume she pulled 60% of the undecideds and that gives her the 52-48 lead that the extrapolation from the original exit polls does.
So it's pretty easy to see where we went wrong. I'm glad that it was misweighting rather than some sort of systematic issue with our polls. Obviously we'll take some heat in the next few weeks for being so far off, and we certainly deserve it, but at the same time I don't think this should completely discount our credibility as a company- we've been pretty darn good a lot of other times this cycle.
Update: I posted this after Fox called the race while the exit polls still extrapolated to four points. Obviously the margin got greater as the night went along. Looks like the two areas where we were particularly off, as might have been expected, were with white women and senior citizens. We showed the race too close with both of those groups in our final poll, and Hillary ended up winning them by the kind of large margin that would have been expected. Live and learn...
We will just move on and try to do better in North Carolina.