Few predicted Trump had a good shot of winning. But political science models did.

Why did so few people see Donald Trump’s win coming?

The polls got it wrong. The major election forecasting models got it wrong (though FiveThirtyEight’s Nate Silver deserved credit for being significantly less certain about it). The political professionals got it wrong. The pundits got it oh, so very wrong indeed.

Oddly enough, though, there were signs pointing to the fact that Trump had a better chance than people were giving him, and they were lurking in plain sight.

They were in well-known political science research on “fundamental-based” factors that has long been used to explain presidential elections.

What the major political science models said

In fact, of the major political science models that try to explain presidential elections, three predicted Trump would win and three others predicted only a very narrow Clinton victory. We ran down their predictions back in August:

• A model by Yale’s Ray Fair, which used economic factors and the party’s time in office, predicted the Republican would win with 56 percent of the vote.
• A model by Stony Brook’s Helmut Norpoth and University of Wisconsin Milwaukee’s Michael Bednarczuk, which used New Hampshire primary results and recent party presidential performance, predicted the Republican would win with 52.5 percent of the vote.
• Iowa’s Michael Lewis-Beck and Hunter’s Charles Tien used economic factors and the president’s popularity, and predicted a very narrow Democratic win with just 51.1 percent of the vote.
• A model by East Carolina’s Brad Lockerbie, which used polling asking people if they expected to be better off financially in the near future combined with the length of time a party’s spent in the White House, predicted the Democrat would just barely win with 50.4 percent of the vote.
• A model by Christopher Wlezien and Robert Erikson was the only one to incorporate current national horse race polling (along with economic factors). Since Clinton led in polling, it was the best for her, predicting the Democrat would win with 52 percent of the vote.
• And a model by Alan Abramowitz used presidential approval, GDP growth, and years each party has held the presidency to predict the Republican would win with 51.4 percent of the vote.

That last one bears special attention, because Abramowitz publicly disavowed his own forecast’s projections, arguing that it applied for “mainstream” candidates and not for Trump. “Donald Trump is far from a mainstream candidate,” he told Vox’s Dylan Matthews in an email. That’s not to beat on Abramowitz here — I also was aware of what these models showed and yet rarely wrote about them, since I shared the opinion that they were probably going to be “off” this year because Trump was just so strange.

Now, it will take some time for the popular vote to be determined, and Clinton may well narrowly win it. But the point is that, in five of these models, these fundamental factors all pointed to a very close race that could conceivably go either way (while the other pointed to a Trump landslide). And yet the punditry and elites all assumed — both because of the polls, and simply because the GOP nominee was Donald Trump — that Clinton had nothing to worry about.

Did (white) swing voters simply conclude it was time for a change?

A notable factor in several of these models is the incumbent party’s time holding the presidency. It’s been notably difficult for any party to hold the presidency for more than two terms in recent decades — since Franklin D. Roosevelt and Harry Truman’s combined five terms from 1933 to 1952, it’s only happened once, with the Reagan-Bush run of 1981 to 1992.

Abramowitz refers to this as the “time-for-a-change” factor. I’m not sure anyone has a convincing data-based explanation of why it seems to exist (and some have disputed whether it even does exist). But if I had to speculate, I’d say that, as the incumbent party holds on to office, there’s a tendency for its supporters to become gradually more disappointed, disillusioned, and divided, while the out-party’s supporters often grow more energized and motivated at the prospect to turn out the incumbents.

This time around, those trends appeared to play out differently along racial lines. Some white swing voters who had twice voted for Obama swung toward Trump, and rural and non-college white voters overwhelmingly turned out for the GOP nominee in a way pollsters didn’t expect. Meanwhile, black voters who backed Democrats weren’t as excited about Clinton’s candidacy, and didn’t turn out at as high levels as in the previous two cycles. And some other voters who disliked Trump felt sufficiently disillusioned by the Democratic Party and Clinton herself to vote for Jill Stein or Gary Johnson instead.

Currently, our political system has fallen prey to depressing gridlock. Clinton herself had been in politics for decades and pretty clearly had no real potential to enact transformative change. Trump, meanwhile, seemed to many (white) voters to have the potential to shake up the system. They concluded it was time for a change. And now we will see just what kind of change they have brought us.