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9.4: Why Do We Have a Two-Party System?

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    134567
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    “In our view, the ideal of popular sovereignty plays much the same role in contemporary democratic ideology that the divine right of kings played in the monarchical era. It is . . . a fiction providing legitimacy and stability to political systems whose actual workings are manifestly—and inevitably—rather less than divine.”

    —Christopher Achen and Larry Bartels (1)

    A Two-Party System and Its Alternatives

    Since the Republican Party’s rise in the 1850s, all American presidents have been either Democrats or Republicans. As a result, political scientists classify the United States as a two-party system, even though it has many political parties. A two-party system is distinct from its alternatives: a one-party system in which other parties are either banned or so hobbled that they can’t compete with the ruling party, or a multi-party system that features three or more parties with a viable shot of participating in government. Modern history is full of one-party political systems like Nazi Germany, the Soviet Union, the People’s Republic of China, North Korea, Vietnam, and Cuba. Multi-party systems exist in many countries like Denmark, France, the United Kingdom, Germany, Australia, and New Zealand.

    Causes of America’s Two-Party System

    Why is the United States a two-party system as opposed to a multi-party one? It is, after all, a very diverse country that could probably support more than two parties. In the U.S., two structural features strongly favor a two-party system as opposed to a multi-party system.

    • ballot-access restrictions, which are any barriers to getting a candidate on the ballot so voters don’t have to write in their name. Natural experiments have shown that when ballot-access restrictions were lowered, the major parties faced significantly increased competition from third party and independent candidates. (3) Many states require independent and third-party candidates to secure enough signatures on petitions in order to get on the ballot. Simply put, “The greater the share of the electorate required to sign nominating petitions, the fewer minor-party and independent candidates appear on the ballot.” (4) A third party that wants to run candidates for all the House seats across the country would have to collect millions of signatures. The Democrats and Republicans are relieved of this burden. Collecting these signatures is expensive and time-consuming. Together, filing fees and signature requirements stunt electoral competition, especially races for the House of Representatives. (5)
    • winner-take-all elections, where a candidate who gets the most votes wins the election. Here is an example. Bill receives 546 votes, Mary receives 545 votes, and Sam receives 544 votes in a U. S. House of Representatives’ election, Bill wins even though he received only 33 percent of the vote. He received the most votes short of a majority, called the plurality of votes, and he will represent that district. The tendency for winner-take-all, single-member district systems to promote two parties is sometimes referred to as Duverger’s Law, after the French political scientist Maurice Duverger.

    How does the winner-take-all system help create a two-party system? Let's look at an example. The Blue Party pushes the interests of the common laborer but has also been somewhat environmentally friendly. The Red Party is a conservative party that pushes the interests of big business and entrepreneurs and is very unfriendly to the environment. The Green Party is very concerned about the environment, and is brand new. Here are the results of our mock election:

    Hypothetical election between Blue, Green, and Red parties.

    What happened? Blue wins two seats by getting the plurality of votes in District One and the majority of votes in District Three. Red wins one seat in District Two. Green gets nothing. The Greens have gone through all the work and expense of getting the party started and getting on the ballot. Can the Green devotees keep the party going for two years until the next election? Maybe. Let’s assume that not only do they keep it going, they actually do a little better. Here are the results for the next election two years later:

    Hypothetical election between Red, Green, and Blue parties.

    The Greens did a bit better, but what did it get them? Still nothing. It’s very difficult to keep a new party going year after year if all that effort is not producing actual legislative seats. In this case, the Green party saw tremendous gains for a third party, but people want to vote for a party that stands at least some chance of winning seats.

    Look what happened in that second election. Green pulled voters away from Blue and guaranteed that Red would pick up another seat even though Red’s support didn’t actually go up. In District One during Election #2, the Green candidate was the so-called spoiler candidate.

    What is a Green voter to do? One choice is to keep voting Green with the hope that the Blue party will self-destruct so that the Greens will be the only real alternative to the Reds. Something like that hasn’t happened in the United States since the 1850s, so its likelihood is not high.

    What If?

    What if we required third parties to gain enough signatures in a state once, after which they would be guaranteed ballot access in perpetuity instead of having to do it each election?

    References

    1. Christopher H. Achen and Larry M. Bartels, Democracy For Realists: Why Elections Do Not Produce Responsive Government. Princeton: Princeton University Press, 2016. Page 19.
    2. See Richard Winger, editor of Ballot Access News, “The Importance of Ballot Access,” archived here. Richard Winger, “Institutional Obstacles to a Multiparty System,” in Paul S. Herrnson and John C. Green, editors, Multiparty Politics in America. Lanham, MD: Rowman and Littlefield, 1997.
    3. Marcus Drometer and Johannes Rincke, “The Impact of Ballot Access Restrictions on Electoral Competition: Evidence from a Natural Experiment,” Public Choice. September 25, 2008. Pages 461-474.
    4. Barry C. Burden, “Ballot Regulations and Multiparty Politics in the States,” PS: Political Science and Politics. October, 2007. Page 671.
    5. Stephen Ansolabehere and Alan Gerber, “The Effects of Filing Fees and Petition Requirements on U.S. House Elections,” Legislative Studies Quarterly. 21(2). May 2, 1996.
    6. See: Fairvote. Ranked Choice Voting Resource Center.

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    9.4: Why Do We Have a Two-Party System? is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by LibreTexts.

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