Such models presumably can be tested in some sense. E.g. build some sort of predictive model of elections in each state using Twitter users as a surrogate, see

Such models presumably can be tested in some sense. E.g. build some sort of predictive model of elections in each state using Twitter users as a surrogate, see how well you do. I'm not claiming that such a model is guaranteed to be perfect or even as good as a pollster, but it sounds in principle like a reasonable thing to do, if you take appropriate precautions to reduce bias.