From the Thursday night Democratic Debate:

MADDOW: Senator Sanders, as a Vermonter, you have almost a home state advantage here in New Hampshire. But back home across the border, you also have a long history of running against Democrats as a third-party candidate, for governor, Senate, for Congress.

In 1988 your candidacy as a third-party candidate arguably cost the Democrats a congressional seat and sent a Republican instead.

How can you lead the Democratic Party nationally when you have not been a member of the Democratic Party until very recently?

SANDERS: Well, Rachel, actually, that wasn’t accurate. In 1988 the Republican did win, I believe, by 3 points. I came in second. It was 34-31, I think, 19 for the Democrat. In that race the Democrat was the spoiler, not me. And it is true…

@AlbertsonB2 Came to twitter just to say this.

— Alex Branham (@JAlexBranham) February 5, 2016

@trumwill ok, not a good answer in my class though.

— Bethany Albertson (@AlbertsonB2) February 5, 2016

Well, if I were in a class I would prefer a response more along the lines of “Show your work.” So here goes…

There is no doubt that we have two main parties. This is not by design, however, as it was not intended by the people who created the system. But it’s not random, because Duverger’s Law ordains that a system in which elections are determined in single-member districts with a First Past The Post System (FPTP) will gravitate towards two parties. This law isn’t ironclad, as the UK and Canada have FPTP elections and persistently have more than two relevant parties, but even they have only had two parties exchanging power over the last decades (counting direct predecessor/successor parties together). The two-party system in the US is further assisted by other factors, such as the independent executive and Electoral College, which make things especially daunting for outsider parties. There have been stretches of time wherein we have not had two relevant parties. We’ve had one party and we’ve had three or more. At some point, either could happen again. Even so, the gravitational force of Duverger, along with custom, will likely pull things back to two parties.

And that’s a good thing, for the most part. Our system works most efficiently when there are two parties. When there are more than two parties, you can get skewed results as seem to have happened in both the UK and Canada in recent elections. And while Americans often look longingly at multiparty systems, I genuinely prefer a two-party system as the best way that voters can make a choice between clear alternatives. In that sense, I am sympathetic to Albertson’s apparent argument. Where I believe that argument falls short is treating the placement of the two parties, and their identities, over the actual preference of the voters. Three-way races in two-party systems do lead to inefficient outcomes, but the two main parties do not have a special right to be the two slots in the two-party system. Ideally we might have a system that allows voters to directly decide which candidates belong in the two-way race (ie runoffs). But short of that, the role of spoiler belongs to the person or party that is least in a position to win.

Which brings us to Sanders’ 1988 election, described by Wikipedia thusly:

In 1988, incumbent Republican Congressman Jim Jeffords decided to run for the U.S. Senate, vacating the House seat representing Vermont’s at-large congressional district. Republican Lieutenant Governor Peter P. Smith won the House election with a plurality, securing 41% of the vote. Sanders, who ran as an independent, placed second with 38% of the vote, while Democratic State Representative Paul N. Poirier placed third with 19% of the vote. Two years later, Sanders ran for the seat again and defeated the incumbent Smith by a margin of 56% to 40%.

By a greater-than 4-to-1 margin, voters prefered either Sanders or Smith to Poirier. More voters supported a Sanders-Smith contest (79%) than a Poirier-Smith (60%) contest. And, of course, voters supported Sanders over Poirier by a 2-to-1 margin. No matter how much we talk about Duverger’s Law, the preference of the people here is clear. When a major political party cannot muster more support than that, it has no divine nor democratic right to a position in the race. If there had been a runoff (as there might be in other states), it would have been Republican vs Independent. The Democrat simply lost. The two-person race that perhaps should have occurred wouldn’t have included him, and there is no particular reason that it should have. More recently in Kansas, the Democrats actually pulled somebody from the race to prevent his presence from tilting the election away from a sympathetic independent with a chance of winning (which didn’t happen).

There is not always a spoiler in a three-way race, of course. The winner may get a majority of the vote (Lieberman ’06, King ’12) in which case it doesn’t matter how their opposition splinters. The third-place finisher may not have siphoned enough votes disproportionately to affect the outcome (possibly LePage ’14, Perot ’92). But if there is a spoiler, that title goes to the candidate of the three who was most rejected by the voters. More often than not, that’s going to be the independent candidate. When an independent candidate actually wins, though, it’s hard to argue that they spoiled anything democratically. The same applies when they get second place. Which, by extension, means that if there is a spoiler, it is not definitionally the independent candidate. When the independent candidate gets more votes than one of the alternatives, the people have spoken in favor of his candidacy and against the party candidate.

The deck is stacked pretty heavily in favor of parties and party candidates. They have the organization and the money. If, despite all of these advantages, they’re running behind someone without them, they don’t deserve to be deferred to. The inefficient outcome, if there is one, is on them. They are the spoiler.