Only if you're going to include most sports betting in the same category.
Why not? Because it's trivial? Nate Silver himself is first and foremost a sports statistician - national elections are a sideline.
Fancy statistical models aren't much different from serious betters parsing the stats. It's prognostication by knowledge of the game, which is how Silver builds his models through heavily weighted and sorted data.
I'm having a hard time reconciling "knowledge of the game sufficient to make accurate predictions reliably" with "not science".
Silver doesn't take straight data as an input, he selects and massages it according to his keen political insights and then makes a model that matches his guesses. Same as someone betting on sports.
If I'm trying to find the gravitational constant
G, I might estimate it at some value, run an experiment, compare the results to what's predicted by my estimate, and then adjust the estimate up or down accordingly and repeat. I am effectively "massaging" the gravitational force in my model. But I'm massaging it
in accordance with experimental results, in order to make better predictions.
If Nate Silver decides
a priori, "My gut tells me Ohio is going to go red", and then weights his data to say that Ohio is going to go red, then you're right, that's not science. But if he does what he says he does, and what we have no reason to suspect he's lying about, then the weights he puts on his data are in response to the results of previous experiments, and will be adjusted in response to future ones, in order to zero in on some value which can make predictions most accurately. That looks like a scientific process to me.
Or casting a horoscope, really.
I'm going to take a stab in the dark and guess that you don't read many horoscopes? The key element of horoscopes and prophecies, the trick that makes them work, is that they make
vague predictions which can can be interpreted after the fact as conforming to whatever happened, and are thus difficult to falsify. Whatever else you may say about political prognosticators, they do not do that. We can say, definitively, what Nate Silver was right about and what he was wrong about. That clarity is in falsification conditions the
sine quae non of science. So to compare a prediction which has such clarity with one which doesn't is deeply unfair and, when the whole point of this discussion is "what is science?", actively misleading.
If you're making a guess about the future, it's no longer history, is it? Under this interpretation, ALL science is history, because it all uses past observations to inform the method. This proves too much.
With apologies to Francis Fukuyama, history did not end in the year 1990. History is the diachronic study of human behavior and societies - or, if I may be tautological in turn, it's the study of the stuff that makes it into history books. Historians have
tons to say about current and future events. They differ from, say, sociologists or political scientists in that their methodology is more focused on finding patterns of cause and effect in the written and archeological record, although naturally the boundary between the disciplines is fuzzy and there's a lot of overlap. But in short, "Those who do not study the past are doomed to repeat it" really is kind of the historian's mission statement.