Let’s imagine, several decades in the future, a third major party in the U.S. rises alongside the Democrats and Republicans, with major grassroots support – just call them the New Guys. How would you imagine politics in the U.S. will change?

Here are some basic things I thought up of:

  • Now the House, Senate, and other positions of power will have three parties vying for control. If they are divided over some piece of legislation or bill, then it will be much harder to achieve a plurality in any group.

  • Suppose during the race for presidency, we have three major candidates, one from each party, all with great support. However, it is clear that one won’t win – but they have enough support to tip the scales if they convince their supporters to vote for candidate A/B. Cue alliances/betrayal.

  • 8
    $\begingroup$ Most non-US countries have at least 3 major political parties $\endgroup$
    – Daniel M.
    Jan 30, 2016 at 4:17
  • 1
    $\begingroup$ They'd likely be very conservative, because at this point both parties are ripe with progressivism and socialism. $\endgroup$ Jan 30, 2016 at 4:31
  • $\begingroup$ You need to implement The alternative vote for this to work. $\endgroup$ Jul 1, 2017 at 20:57

3 Answers 3


Either the US would switch voting methods or one of the three parties would die.

First-past-the-post voting methods with separate voting for the executive inherently lead to two party rule (Duverger's law). The reason is that there is no way for three parties to field viable candidates. What inevitably happens is that one of the parties merges into the other two, usually mostly into one.

Let's look at previous parties:

  • Federalists: The first political party in the US. Had support from Washington supporters like John Adams. Only had one member become President (Adams). Died in the face of the Democratic-Republicans.

  • Democratic-Republicans: Jefferson through John Quincy Adams were this party. It was replaced by the Democrats.

  • Democrats: Andrew Jackson dropped Republicans from the name.

  • Whigs: Replaced the National Republicans who replaced the Federalists. Was itself replaced by the Republicans. A minority party in 1860, it was gone by 1864.

  • Republicans: Formed out of the ashes of the Whig party as the abolition party.

The Republicans are pretty much the only successful third party. The Whigs wouldn't adopt an abolition plank, so the Republicans split off. The Whigs died. Since that time, there have only been two major parties, although others have attempted to form. Some examples:

  • Progressives: Theodore Roosevelt left the Republicans and formed his own party. They played spoiler, allowing Democrat Woodrow Wilson to take the presidency in 1912 despite winning a majority in only eleven states. Wilson's plurality wins in twenty-nine other states carried him to a 435-96 landslide. Only had a few office holders. Gone by 1920.

  • American Independents: George Wallace's party. Took enough of the vote that if he could have merged with either other candidate, they'd have won the popular vote. But Nixon was the plurality winner in seventeen states and majority winner in fifteen more. Wallace's voters had mostly been Democrats previously but are believed to have voted Republican most of the time after this. No office holders.

  • Reform: Ross Perot's party. Never won a state. One office holder: Governor Jesse Ventura of Minnesota.

No third party in the US has ever persisted for more than a few elections without becoming one of the top two parties. As I said earlier, the reason is that the first-past-the-post system of plurality wins doesn't encourage the kind of vote swapping that occurs in other places. It is natural for any three party system to fall back into two parties given the voting system in the US.

In European systems, this is different. It is easier for smaller parties to get representation, and in parliamentary systems, it makes sense for coalitions to form after the elections. In the US, coalition building occurs before the election. After the election, typically all the seats are won by the major parties.

Anyway, to get back to the question, if you want this in the US, you need to change the voting system. The most likely change that is reasonably practical would be adoption of multi-candidate voting districts with proportional representation.

A very narrow possibility would be a regionally strong party. However, most parties haven't been that strong regionally. Their strength tends to be too dispersed.

Note that the most natural way to cement an alliance between two parties in the US is by sharing a presidential ticket. The third party representative would be the Vice-President. Of course, that can add to the assassination danger.

House and Senate voting isn't based on pluralities. A majority of those who vote have to support the legislation in the House and a super-majority of 60% in the Senate. Two parties could join together to pass legislation, assuming that between them they have 60% of the Senate. Note that in the current system, the 60% rule almost always means that there must be some minimal level of bipartisanship.

A third party might make that easier. Instead of having to join with the major enemy, a major party could join with the third party.

Since the Senate is run by the majority conference, the third party could choose with whom to join. So they'd almost always get space on the majority conference's committees.


I suspect that the answer in the United States might well be that only two parties survive, but suspect that it is more because of cultural and historical factors rather than any inherent design in the system.

Multi party states exist all over the world, and in a multiplicity of voting schema. Multiple political parities work best in various forms of Proportional Representation, since even very small petites with a tiny number of voters can exert immense political power by offering up their seats in Parliament (and thus votes) to support the ruling coalition in exchange for support for their more extreme/radical/minority positions. Full PR systems like Italy or Israel can see parties with as little as 5% of electoral support take cabinet seats and impose their views as part of the price for governing coalition to continue in power.

First Past the Post systems with multiple parties also exist, for example Canada and the UK. At one point in the 1990's, Canada had a total of five political parties sitting in Parliament (the Liberals, Progressive Conservatives, Reform Party, New Democrats and Bloc Quebecois). Through vote splitting and the leading party "coming up through the middle" (the Progressive Conservatives and Reform parties were both right wing, while the New Democrats and Bloc Quebecois were left wing and the Liberals ran as centrists), it was possible to achieve majority governments, but it would have equally been possible (in a Westminister style Parliament) to have a minority government which would be beholden to one or the other opposition parties in order to pass legislation. Clever minority leaders often make deals across both sides of the aisle in order to pass various pieces of legislation. Readers of British history will recognize similar situations, and of course there are multiple parties sitting in Parliament in the UK today.

The United States has one complication which I am not really qualified to answer, however. The office of the chief executive, the President of the United States, is down through the system of the Electoral College. This was instituted so that smaller States would not have their influence swamped by the popular vote of larger, more populous States. I am not clear of the mechanism for the electoral college to handle a multiplicity of candidates. On the other hand, should there be a deadlock in the Presidential electoral system, the Constitution has a clear line of succession, from the Vice President (mooted in the case of an electoral college deadlock) to the Speaker of the House. In that case, the Speaker would become the leader of the United States unless and until such time as the Electoral College could sort out the situation of the Presidential election.

In the House and Senate, third party Congressmen and Senators will have the option of throwing their support behind either of the mainstream parities depending on what bill is being voted upon, their "alignment" and how large they actually are (a party with one or two seats will not make much of a difference, but a party with a block of 50+ Representatives or 30+ Senators will make a huge difference in their respective house). Expect a lot of "log rolling" and other dealmaking to go on behind closed doors to secure these votes, and the President should be very adroit in securing allies in the Congress, or prepared to use Veto power extensively if the Third Party is philosophically opposed to the President.

  • 1
    $\begingroup$ The Speaker does not become President if no one wins the electoral college. In that case, the House elects the President and the Senate elects the Vice-President. It's never been used though, as the one time it seemed to be happening, several candidates merged behind John Quincy Adams. $\endgroup$
    – Brythan
    Jan 30, 2016 at 23:03

So from the perspective of the voters, I don't think much will change. As it is, the United States is fairly evenly split between Democrats, Republicans, and Independents/Unaffiliated voters (note: In this case, it is not the same as the American Independents party. These are strictly people who are registered to vote, but are not registered to vote for a party. They are unable to partake in closed primary elections, which are party exclusive.). To this extent, the I/U vote is quite important, as they tend to swing their vote and currying favor with them, especially in swing states and also tend to follow politics quite closely and examine both sides with some degree of scrutiny (seriously, if you want to feel like the most important person in the world, be a registered independent in a state like Florida... the candidates treat your opinion like it actually matters. I once got one party to stop spam calling me for two weeks by threatening not to vote for them if I heard from them between now and the time I go to the polls).

From a government standpoint, it would most likely first be noticed in the House of Representatives. They are the party of the people and should the third party be popular enough and strong enough, can take a significant chunk of seats in an election year (turnovers tend to happen in the mid-terms, when the President is not up for vote). Since they have a smaller constituency, it is rare for a state to have a solid House Deligation of one party. During the 2016 election, only five states (not including DC) saw a single party majority across all jurisdictions in the Presidential race.

The senate will take longer. If a state becomes a strong state for a full senatorial flip, it will take anywhere for four to six years, depending on how the state is staggard for elections (in a six year period, you will elect both senators once, but never in the same election year, and have one year where niether is up for vote).

Presidentially is where it gets interesting especially from a political standpoint. To become president, you must secure 270 electoral votes (each state gets two electoral votes (one for each senator) plus one for each represntative. It should be noted that electoral votes are not the senator/represtative. With a Third Party, it is likely that neither candidate can reach 270 of 538 electoral votes. If neither candidate recieves this vote, than the House is called into immediate session for what is called a "Contingent Vote" which is initially held among the three candidates with the most electoral votes. Each state deligation gets one vote for a total of 50. To win, the candidate must recieve 26 votes out of 50. Congress will continue voting and deliberating until such an event occurs. The vice-President is chosen in a similar fashion in the senate, with the difference being that it only considers the two leading VPs and all senators recieve a vote (winning requires 51 out of 100).

Having a viable thrid party will likely mean that a vast majority of Presidential administations will be made this way (assuming that the viable third party, hence forth called the Viable Party, pulls equally from both likely Democrat and Republic voters. If their base is more reliably to one party, it's really just changing the name of a party in a two party system). Since the President must be chosen by states voting together, individual delegations must first decide who they will vote for and then there must be enough deligations to achieve a majority... depending on how contentious a fractured trinary system is in congress, this could go on for some time. Should the President-elect and VP-elect not be chosen, congress will chose who will be Acting President until they can come to a choice (traditionally, the VP of the incumbant andministration, as this was once part of the constitution, but is no longer written as a rule... Congress can pick anyone). The Acting President title is rather contentious and only two people in history (George H.W. Bush and Dick Cheyne) have ever officially been called it (John Tyler is often considered but as a VP following the death of the president, he just called himself President and had it. Bush and Cheyne both assumed the role while Regan and George W. Bush (respectively) were sedation for surgery. Notably Bush SR. did not assume the role during Reagan's assasination, despite having the authority to declare it, because he felt it might be seen as a coup... but essentially was the CiC for the duration of Reagan's incapacitation.). Whoever becomes the Acting President will remain so until either a President is properly chosen OR a Vice President is properly chosen, who will assume the Acting President role until the President proper is chosen.

Back to the people, this may not be an experience the country will enjoy and may be a time of unrest and calls for changes to how government is run to come into play. Little of merit will get done, as Congress must choose head of states and if the affair goes on for month, important legislation may be put aside. Other countries may see this as a moment of weakness and sieze upon diplomatic opertunities to fill the void of a stalled United States.

On the benefit side, with a third candidate from the Viable Party, the political rhetoric of the country may be tempored as Democrats and Republicans must cort indpendent-leaning voters away from two rival parties instead of one. States where one party is dominant over the other may find a bigger chance to flip if the Viable party appeals to moderates of the dominant party.

To make voting a bit more likely to favor a third party candidate, it might be changed to Instant Run Off votes (currently Maine is the only state that has them at national level). Essentially if Candidates A, B, and C are on the ticket, then the voter will order them in order of preference (i.e. I vote B as my first choice, C as my second choice, and A as my last choice). Should no majority occur, the candidate with the least votes will be eliminated and all votes for him will be distributed to the second choice of each ballot (assuming B is the weakes, my vote will go to C. If you ordered differently, than A will recieve your vote... assuming C was your first pick). For more than three candidates, leaving blank one candidate will mean he will never recieve your vote (The idea is you're more likely to vote for a third party if neither of the two mainstream parties curried your favor. If the Democrat and Republican party candidates are both pretty unlikable, voting for a third party might be more viable if you could still give it to a candidate if the TPC didn't perform well... might have changed some outcomes.).


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .