Where we find ourselves the day after the election is no surprise. Some state results are delayed, as we knew they would be. And the presidential race is very close, as we also knew to expect — or certainly should have known.

Yes, yes, the polls. The polls gave Democratic nominee Joe Biden a strong and consistent lead over President Trump, both nationally and in swing states like the six whose final tally remains unknown as of this writing. But whatever is going wrong with the polls, be it problems of collection or calculation or lying participants or all of the above, a landslide for either side was never likely.

So why did so many people think it was? Why did so many Democrats daydream of a national realignment over the last four years — one large enough to give Biden Electoral College counts north of 350? Why are so many Republicans stunned their man might lose or convinced a Trump loss could only happen by fraud? The explanation for both the closeness of the race and the unwarranted shock it's producing is what Stanford University political scientist Morris Fiorina calls "unstable majorities."

Fiorina's idea has several elements. One is that the rising partisanship and polarization we all see in American politics is real, but it's also concentrated in a smaller and more disproportionately vocal portion of the population than we often realize. Meanwhile, though we only have two major parties, the American electorate is divided into thirds, not halves.

"I think it's fair to say we have — if you take turnout into account — we now have a one-third, one-third, one-third party system," Fiorina said in a 2018 interview with Reason. "The Democrats have a third; Republicans have a third; and a third are in the middle." The middle third, independents, is actually a slight plurality of about 40 percent. And though it may include some closet partisans, Fiorina allowed, the bulk of this group truly does vote independently, bouncing between the big parties and sometimes going for third-party candidates or sitting out elections altogether.

Forcing three groups to choose between two viable options produces chaotic results. In decades past, when the major parties were less polarized and the electorate less dissatisfied, American presidents could claim a popular vote victory margin of 10 percent or more and an Electoral College map with just a handful of holdouts, usually regionally concentrated. This happened for both parties — see the results, for example, in 1940, 1956, 1964, or 1980. There were close races, too, but something like 1972's 49-state sweep by then-incumbent President Richard Nixon was possible. It is not possible now.

Instead what we get is mixed government, mismatches between the popular vote and the Electoral College outcome, and a nation perpetually careening from one party to the other. Candidates are still trying to do the old playbook of appealing to their base in the primaries, tacking back to center for the general election, and then governing somewhere in between. But it doesn't work anymore. The partisan bases are increasingly distant from the center, and now-ubiquitous recording of candidates' every utterance means any move toward broader appeal is met with howls of partisan objection. (Biden's painful dance on court-packing is an excellent case study here.)

"So you win the election by capturing the lion's share in the middle," Fiorina explained to Reason, "but then if you impose an agenda that's your base's agenda [once in office], a lot of the people in the middle say, 'I didn't really vote for that,' and they abandon you in the next election." Or, as could yet happen in this cycle, they split control of Congress and the White House, seeking something like centrism and settling for a miserable gridlock of warring extremes. Unable, thanks to institutional barriers, to elect a president with an agenda in between that of staunch Democratic and Republican partisans, the independent third tries to jury-rig its approximation by jumping back and forth between the options on offer. If the oil and water won't mix, just shake 'em up real good.

This solution, such as it is, is mysterious to many in the partisan thirds, the very people pushing the major parties' polarization. The most activist partisans like the moves away from center, particularly on culture war stuff like abortion, race, immigration, religious liberty, the COVID-19 pandemic, and LGBTQ issues. They like power politics in which compromise is unacceptable because crushing the enemy is the point. Moderation to appeal to the independent third is unacceptable in this mindset — or it would be, if the necessity of moderation were ever seriously considered.

Instead, these two partisan minorities both campaign and govern as the majorities they are not. They envision the political median far closer to their own location than it actually is; conceive of their partisan enemies both more extreme and rarer than they actually are; and fail to adequately reckon with the volatile dissatisfaction of the independent third. This is all very well-received inside the base and makes for electoral fantasies of presidential landslides. It also produces the instability Fiorina postulates.

And so, whether Trump or Biden prevails, the resultant majority will be unstable, barely deserving the title "majority" at all. As I write this, the probable but still-uncertain outcome is a narrowly triumphant Democratic president, a narrowly Republican Senate, a Democratic House, and a conservative-majority Supreme Court. State legislatures and executive triplexes will be similarly mixed.

Even if the presidency goes the other way, there's no national mandate here, nor is there any huge shock. The independent third has simply made its conflicted choice. But don't be surprised if, by 2022, the oil and water are in for another good shake.

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