IIRC, Cohn mentioned one of the downsides of this type of polling is that it fails to pick up on new registrants, which would miss a recent surge in Hispanics registration. That alone probably wouldn't yield a Trump +4 lead though.
That's correct. They use voter registration file so it won't pick up the most recently registered voters.
But nonetheless, 4 point lead is huge.
That should be a negligible effect though. The biggest difference in this poll is that it weights to party registration, which it notes, lots of other pollster don't. Remains to be seen how accurate this will turn out.
