I suspect that the Republicans are winning elections using a simple and legal scam:
They simply tell their most loyal people to lie when answering polls. i.e. to say that they will vote for the democratic candidate.
TRANSLATION: I have no evidence that this occurred, or anything like it. But I really wish it did, so I'll push it as something "likely". Instead of telling the truth: That Hillary was a piss-poor candidate who couldn't even beat a businessman who wasn't even a politician; and the news media was incompetent in drawing up its polls.
The news media doesn't take polls. they report the results of polls which are taken by companies that specialized in polling.
These companies have expert statisticians, which of course means nothing to people who don't believe in math and science and stuff like that, but to those of us who do, there is a great concern as to why these polls did not match the election results.
One theory is to say that the pollsters do not know what they're doing. The problem with that is that in the vast majority of electoral districts the polls were absolutely accurate. They were only inaccurate in key electoral district - very suspicious.
The next is to say that there was election fraud - this would have had to occur on a massive level and would mean a total vulnerability of our election system. It's not impossible, but it's highly doubtful.
So, I've come up with an alternative - and very simple and realistic theory. The elections were accurate, the polls were accurate but people just lied when they were polled. Because it would mean only people of one political persuasion and only in key electoral districts, it would have to be organized. What's more is that since it's not illegal to lie on polls - it's much more probable than any other explanation.