There are a number of structural reasons why the American political system is a two-party system and any attempt at creating a third major party have not been sustainable. The core of the issue revolves around the US system of winner-take-all elections. This system has four main attributes.
First, there are single seat districts. This means that each candidate runs for one specific seat in an elected body. For example, if Illinois has 10 seats in the House of Representatives, that means that Illinois is broken up into 10 different geographic districts. Each voter resides in a specific district and can only vote for candidates that are running for the seat that represents that district.
Second, the candidate with the most votes wins the seat. This means that there is no majority requirement. If there are 10 candidates and they each get one vote except for one of them that gets two votes, the candidate that received two votes would win even though the overwhelming majority of voters voted against them.
This leads into the third point, that there are direct elections. This means that the general population chooses the officials directly. As a result, elections are very expensive to host since you have to print ballots for each possible voter, mail ballots to voters that request them, advertise voting details, hire people to staff polling stations at locations and times that are convenient for voters, transport ballots and supplies, count the votes, and perform manual quality assurance recounts. That doesn’t even include the government costs of infrastructure like voting machines and maintaining voter registration databases or the costs to voters in terms of time and effort required to vote. This makes it cost prohibitive and impractical to host multiple rounds of voting. Because there are not multiple rounds of voting, voters have to consider the likelihood of their candidate getting elected since they will be unable to change their vote to their second or third choices if their preferred candidate is eliminated.
In presidential elections, there is also a fourth aspect, which is the electoral college. Since the president is elected by electoral votes that are mostly allocated in a winner-take-all manner at the state level, some states and voters are far more important than others. For example, each vote in Florida, a traditionally highly contested swing state, is far more important than a vote in a state that is not competitive and always votes for the same party. This also means a presidential candidate can win the popular vote but lose the election like Al Gore in 2000 when he got over half a million more popular votes than George W. Bush but still lost the election by five electoral votes. NPR calculated that a candidate can win the electoral college with as low as 23% of the popular vote.
The American system stands in contrast to many international systems where more than two parties thrive. The systems with more than two parties typically have three main differences from the American system in the way that their officials are elected.
The first difference is multi-member districts. In its rawest form, this means that voters cast multiple votes for multiple candidates to fill multiple seats in a given governing body. To return to the Illinois seats in the House of Representatives example, this would mean that if there are 10 seats, each voter gets to vote for 10 candidates, and the 10 candidates that get the most votes are the ones that get the seats. In America, some elections for things like local school boards are conducted in this manner where you get to choose multiple candidates.
The second difference is proportional representation. Proportional representation means that even if a party does not receive the most votes, they still get seats in the governing body related to the portion of the vote that they received. This makes minor parties relevant beyond elections and gives them some ability to directly work on enacting their policies without going through representatives from other parties. All multi-member districts are proportional to some degree since candidates don’t have to receive the most votes to take office. One of the fairer ways to proportionally allocate seats in multi-member districts is by having voters cast their votes for a party instead of specific candidates. Seats are then allocated to each party based on what percentage of the vote that party receives and that party’s members choose which representative they want to fill that seat. In our Illinois example, if the Democratic party gets 40% of the vote, they would get four seats, then members of the Democratic party would choose Barack, Bernie, Bill, and Hillary to fill those seats. If a third party such as the Green party gets 10% of the vote, they would get one seat, and their members would choose Jill to fill it.
The third difference is multiple round voting for positions that only have one opening. The most common way to do this is by having a group of representatives gather in one location and keep voting over and over while eliminating the lower performing candidates until one candidate gets the majority. The downside of this option is that people are not directly electing all of their leaders. This might not make sense for local or minor elections though since there are both time and monetary costs associated with gathering the representatives. An example of multiple round voting in the US is how parties hold conventions to select their Presidential candidate after the primary voting has completed.
There is also another way to have multiple rounds of voting that still allows the population to directly elect all officials at all levels without the costs associated with having voters cast more than one ballot. The general population could rate all of the candidates and order them from first to last choice. When the ballots are counted, they would use each voter’s first choice in the first round of voting. At the end of that round, they would eliminate the lowest performing candidate. In any further rounds of voting, they would use the voter’s highest choice that had not yet been eliminated and repeat the process until one candidate gets the majority. The downside of this option is that it is much more complicated to count. Ranked choice voting was just implemented in Maine for the 2018 primaries and federal elections. It is also under consideration in a number of other places.
These types of systems with more than two parties can often be identified by having a parliament, governing coalition, and prime minister. Because there are more parties, the chance of any one party having a majority and being able to pass laws on their own is much lower. As a result, parties have to work together and strike deals in order to advance their own agendas. These parties have to come together to form a governing coalition that between them control the majority of seats in the parliament. They then elect a prime minister to be the head of state. The prime minister is normally the leader of the largest party in the governing coalition. Examples of countries with these types of systems include Israel, Japan, and the UK.
Because direct presidential elections are inherently single district winner-take-all since there is only one president for the entire country, the head of government in parliamentary systems is typically a prime minister that is elected by the parliament. This parliamentary system of electing a prime minister is actually very similar to how the electoral college works at the national level in American presidential elections. At the state level, all states currently use winner-take-all systems to allocate their electoral votes. However, electors in many states are not actually bound to follow the results of the popular vote in their states. A presidential candidate must also receive the outright majority of electoral votes in order to become the next president.
If no candidate reaches the required majority of electoral votes, there will be a runoff election in January where the newly sworn in House of Representatives chooses one of the top three presidential candidates to be the next president. The new Senate chooses the next vice president from the top two vice presidential candidates since votes are technically cast separately for the president and vice president. This could result in the president and vice president belonging to different parties. The last time Congress selected the president was the 1824 election of John Quincy Adams, when America’s first political parties were just starting to form and there were four presidential candidates.
Traditionally, only having two major parties makes them both fairly moderate so that they can appeal to the independent and swing voters that typically decide elections. However, politicians are the ones that decide where the legislative boundaries between districts are drawn in most states. Since the party in power has detailed information on where the supporters of each party live, in recent years they have turned to gerrymandering, a tactic that has been around for a long time but become more prominent in recent years as the amount of data and detail it contains on voter preferences has increased.
Gerrymandering is the practice of drawing district boundaries not on the basis of geography or logical neighborhood boundaries, but based on the number of voters for each party on a given block. The goal of gerrymandering is to give yourself the greatest chance to win the most possible seats. This is generally done by conceding certain districts and putting as many of your opponent’s supporters in those districts you are conceding as possible. An easy way to spot gerrymandering is the presence of long, narrow, and twisting districts.
In many countries with winner-take-all elections, gerrymandering is not a factor because the maps of district boundaries do not move, or if they do move, they are changed by an independent, non-partisan redistricting committee comprised of experts. This contrasts with the majority of the United States, where politicians are responsible for drawing legislative district boundaries. The redrawing of those boundaries happens every 10 years after the Decennial Census. This allows the politicians in charge during the redistricting year to protect their party’s power for the following decade. Recent effects of this were documented by the Associated Press in the 2018 election.
The end result of gerrymandering is that many districts have so much support for one particular party that the primary election is more contested than the general election. This allows fringes within the party to pull the party as a whole away from moderation and towards the extremes. One of the biggest examples of this was in 2010 when the Tea Party candidates defeated a number of more moderate Republican incumbents in primary elections. In competitive districts, these candidates on the political extremes tend to lose when the other party’s candidate is more moderate since the more moderate candidate normally wins the independent and swing voters in the general election. However, since many of those districts are not competitive, the Tea Party candidates won many of the general elections anyway. As a result, politicians in these non-competitive districts know that if they compromise across party lines, there is a good chance they will not withstand primary challenges from more extreme candidates.
As a result of gerrymandering and in order to reduce the influence of the more extreme wings of political parties, many states are trying to have non-partisan groups draw legislative district boundaries based primarily on compactness and continuity. The problem with these efforts is that the politicians currently in power have a vested interest in maintaining the status quo. As a result, the most successful efforts have come from constitutional amendments passed directly by citizens. However, politicians are fighting tooth and nail to keep these initiatives off of the ballot despite broad bipartisan support among citizens. One example is the Independent Map Amendment in Illinois.
Given all of the impediments they face, the next logical question is why third parties exist and what their function is in the American political system. Their function is to be incubators for new ideas. Once an idea gains enough support, it is typically adopted by a major party in order to recruit that idea’s supporters. This also reinforces the two-party system because the growing third party’s supporters leave that third party for the major party that actually has power in the government and can fight for that idea.
As far as how third parties have performed in elections, here are some of the most notable historical results. The candidate with the most popular votes was Ross Perot in 1992 with 19.7 million votes for 18.9% of the popular vote. However, he failed to get a single electoral vote despite getting three times as many popular votes as the popular vote margin of victory that pushed Democrat Bill Clinton to victory over incumbent Republican President George Bush.
The most electoral votes for a third party candidate was when former two-term Republican President Theodore Roosevelt ran for a third term as a member of the Progressive Party in 1912. Roosevelt got 88 electoral votes with 4.1 million popular votes. This cannibalized the re-election bid of incumbent Republican President William Taft who got 3.5 million popular votes. The end result was Democratic candidate Woodrow Wilson winning in an electoral landslide despite his 6.3 million popular votes being significantly less than the combined total of Roosevelt and Taft.
The most recently controversial election was the election of Republican candidate George W. Bush in 2000. Democratic candidate Al Gore won the popular vote but lost the electoral vote after a lengthy recount process in Florida. Many accuse Green candidate Ralph Nader, who got 2.8 million votes, of playing spoiler and being the reason that Gore lost. This is because Nader received far more votes than Bush’s margin of victory in a number of states and Nader’s supporters were far more likely to vote for Gore than Bush as their second choice candidate.
There are countless other examples of independents or third party candidates that ran to the extreme of a major party candidate and received substantially more votes than the amount that the major party candidate lost by. Instead of trying to get some voters that would ordinary vote for their opponent to vote for them, some major party candidates have instead tried to decrease the number of votes their main opponent receives. This is done by trying to push the voter even further away from themself on the political spectrum and towards a third party candidate that is their ideological opposite in order to siphon away votes from their major party opponent. For example, a Republican might try to redirect progressive votes away from their Democratic opponent to a Green party candidate or a Democrat might try to get conservatives to vote for a Libertarian.
One important thing to note is that the natural state of a winner-take-all system like the American political system is as a two-party system but it doesn’t matter which two parties they are. What those parties call themselves or what their stances on the issues are is completely irrelevant. There are numerous historical examples of a new party rising to replace an old one (Federalists, Whigs, Democrats, Republicans, etc) or a party changing their stances on issues like how Republicans ended slavery under Lincoln but supported segregation as part of the Southern Strategy under Nixon.
Given the structural issues associated with a winner-take-all system, the entrenched incumbency, and all of the historical evidence, it is clear that the simple arguments of more people need to vote for third parties, they need more media attention, or they need more money will not result in any sort of meaningful and sustainable change. Even if a third party rises to prominence in the current winner-take-all system, in short order the smallest of the three parties will effectively merge with another major party to return the system to its two-party equilibrium.
Two fundamental structural changes are needed in order for the US to have more than two sustainable parties. First, there would need to be a complete constitutional overhaul to turn Congress into a parliament with multi-member districts and proportional representation at both the federal and state levels. Second, there would have to be some sort of fair multiple round voting in presidential elections. Either states would have to award electoral votes proportionally and there would need to be an acceptance of Congress choosing the president if a candidate does not receive the majority of electoral votes or voters would have to rank all of the candidates and do away with the electoral system all together. Short of those changes, we are always going to have a system with just two major parties.
