And yet you could say the same about Trump and the RNC. "How could they have not seen that Trump was going to win"? Right up to the first post analysis after polls closed, you had a
Republican within Trump's circle saying that he needed a miracle to win. Trump and the RNC didn't poll the racist base, because the racist base was bloody well hidden.
And yet you're saying that Hillary's campaign should have seen Trump's racist base beating out the staunch Rust Belt Dems and the Hispanics in Florida? Sure, they should have been more willing to step outside their bubble. But it's crazy to say that they should've seen the racist wave coming.
Now, you do bring up the point of us saying that it was obvious, and I think the issue we run into is that the anecdotal evidence on the ground and in the news reports was different to the statistical evidence and data they had at the time. When everyone reads stories of Trump supporters loving his pussy-grabbing antics, then we can go "What the fuck?" But the data Hillary had didn't support that groundswell. Did they over-rely on it? Yes. Was it a bad mistake? Yes. Was it an
understandable mistake? Mmmmm... Yes? No? Hindsight is 20/20 and all that, but you can guarantee that future Dem candidates won't rely on the data-driven Obama-style machine quite as much as Hillary did.
Edit: That said, Dem turnout in Florida was crazy-good, and that probably owes much to the data that the Hillary campaign had. So, what to do? I really want to get into the DNC as an analyst - I think a lot of good analysts, spread-out in varying degrees of closeness to the inner-campaign circle to prevent a bubble-view, could help immensely.