More Thoughts on American Governance: Why Do We Have a Two-Party System?
I recently had a discussion with a professor of mine on how and why our political system barely functions, as evidenced by the unprecedented phenomenon of refusing to vote for raising the debt ceiling without massive concessions in return. (Also evidenced by everything Congress does, but we’ll keep it at that.) Naturally, the topic of our political system being confined to its current two-party reality came up. A lot of people, whether they happen to thoroughly follow Washington or not, agree that a political system with a more robust offering of ideological parties would be better than the status quo. Although people’s reasoning for why this would be so isn’t always necessarily anchored in reason, this opinion seems to be popular.
I’m not positive as to whether this has been adequately polled or not but there is at least this from May 9th by Gallup, which is still telling:

Back to the conversation: After listening to my complaints, this solution to the problem was brought forth. As is most commonly the case when it’s brought forth, though, it’s done so in a way that errs on the side of simplicity. If we want to add more political parties to the mix, we need to understand why the system is the way it is currently. The framers didn’t put into our constitution a clause that mandates a two-party system. In fact, they didn’t say anything whatsoever about political parties.
Unsurprisingly, it’s more nuanced than voters not biting the bullet and voting for a third party’s candidate en masse. Stripped down to its most basic level, we elect members to the House of Representatives and the Senate and the Presidency through a voting method called first-past-the-post. It’s simple: there’s a pool of candidates, you vote for which one you like, the guy or gal with the most votes wins. This style of voting militates toward our unsavory two-party system; Duverger’s Law, via Wikipedia:
A two-party system often develops from the single-member district plurality voting system (SMDP). In an SMDP system, voters have a single vote which they can cast for a single candidate in their district, in which only one legislative seat is available. The winner of the seat is determined by the candidate with the most votes. This means that the SMDP system has several qualities that can serve to discourage the development of third parties and reward the two major parties.
Duverger suggests two reasons why single-member district plurality voting systems favor a two party system. One is the result of the “fusion” (or an alliance very like fusion) of the weak parties, and the other is the “elimination” of weak parties by the voters, by which he means that the voters gradually desert the weak parties on the grounds that they have no chance of winning.
To put this into real terms, by voting for a Green Party candidate or a Libertarian in the U.S., you are wasting your vote. Furthermore, (using the left side of the spectrum in the U.S. as an example) by voting for a Green Party candidate, you are doing more harm than good than if you voted for the Democrat, even if you don’t totally agree with the platform of the Democratic candidate. Principle be damned, you’re hurting your cause. This is essentially the root of the saying that I’m sure everyone hears a hundred times every couple years: “voting for the lesser of two evils”.
If we want to get serious about political reform in the United States then we’re going to need to examine how we vote and, minus something genius from a crafty political scientist, change it. I suggest something along the lines of IRV.
It also needs mentioning that this steps aside the larger, institutional problem with our legislature, which would prevent the addition of more political parties from effecting any substantial progress. That is for another time, though.


As I’ve written previously, the United States Senate doesn’t work anymore [see the most recent post besides this, or the old blog]. This is due in large part to the adoption of the scorched-earth politicking of the minority parties of recent, which includes, but is not limited to, rampant use of the filibuster. As seen in the above graph
Peter Orszag, former OMB Director for President Obama, 