Univac: What went wrong?
In 1952, a Univac computer, with some relatively primitive algorithms and less less raw computing power than most modern appliances, correctly predicted the results of the election hours before final returns were known and in stark contrast to the predictions of human experts.
Somewhere along the way, we lost that ability: polling in the last few election cycles has been pretty weak as a predictor, and we've got millions of times more computing power and immensely denser and better data to work with. Even the most direct comparison, election-night exit polling, failed miserably last time, and not just in Florida.
Are the races really tighter? Is that the problem? Or are we outthinking ourselves: has the Heisenberg effect (I know, physicists hate it when social scientists use this shorthand, but it's not going away) overwhelmed our statistical models so that the ubiquity of polling is its own downfall?