Instant Runoff Voting: How Does It Work?

The instant runoff voting method (IRV) allows voters to express their degree of preference for more than one candidate on the same ballot. When instant runoff voting — or ranked choice voting — is used, there is no need for a second ballot. IRV maximizes voter support for the winning candidate while reducing the cost and delay of holding a second election. In states that allow for an absentee ballot, allowing absentee voters to use an instant runoff ballot ensures their votes count.

How Does Instant Runoff Voting Work?

On an instant runoff ballot in which candidates are running for a single office, all of the candidates are listed on the ballot and voters are asked to rank the candidates by order of preference. The candidate they most want to win will be ranked as their 1st choice, their second choice is 2nd, and their third choice is 3rd. Then they cast their ballot as usual.

Why Do Parties or States Use Instant Runoff Voting?

Political parties want to get the best possible candidate on the ballot in order to improve their chances of winning an election. One of the ways they try to ensure that the best candidate moves forward in a primary election is by setting voting thresholds. Some states/parties require that a winning candidate receive 50% or more of the vote; some require 40%; some require only a majority.

In an election where multiple candidates are running for the same office, it is quite possible that no candidate will achieve the required percentage of votes. (This is often the case in a primary election, and sometimes in a general election.) In order to arrive at a winning candidate, a runoff election will be needed.

But a runoff election has challenges. Runoff voting is held on a separate day to enable new ballots can be created. If the election is one in which voters can vote by absentee ballot, voters will need time to request a runoff ballot, receive it by mail, fill it out, and mail it in. The same voters who cast a vote in the first election may not come back to vote a second time, so the second election may not accurately represent the support the candidate will receive in the general election.

Instant Runoff Voting Example

The ballot for ranked choice voting looks different than a typical ballot.

When the votes are tallied, the first-choice votes are counted first. If one candidate receives the required majority of votes, that candidate is the winner. If no candidate wins the required percentage of votes, the lowest vote-getting candidate is dropped from the ballot.

Another round of tallying begins. If a voter casts a 1st ranked vote for the candidate who was dropped, that person's vote will now be allocated to their 2nd choice candidate. When all votes have been allotted, if the 1st and 2nd choice votes added together now result in one candidate meeting the voting threshold, that candidate wins.

If no one achieves the required majority, the next lowest vote-getter is dropped and the tallying begins again. This continues until there is a clear winner.

This video from Minnesota Public Radio demonstrates how it's done.

How Can Ranked Choice Voting Be Used for Elections With Multiple Winners?

Sometimes more than one candidate is needed to fill an office. For example, there may be four open slots on a school board or water board, and seven candidates may be running to fill those positions. Ranked choice voting (RCV) can be used to determine multiple winners.

The instant runoff ballot in this instance will list all the candidates, but it will ask voters to rank the number of candidates needed for the number of open offices. In the example of seven candidates for four positions, the ballot will ask the voter to rank their 1st, 2nd, 3rd, and 4th choice. The remaining candidates will not be ranked.

How are votes tallied in multiple-winner elections?

In ranked choice voting for multiple winners, tallying of votes becomes a bit more complicated. The process begins by taking the total number of votes cast and dividing that number by the number of offices to be filled. For a candidate to get a majority of the vote, add one to that number. This, then, is the voting threshold that each candidate must meet. This number is the goal.

Now all the 1st choice votes are counted to see which candidates meet the threshold.

  • If four candidates meet it, then each of those candidates wins.
  • If no candidate achieves the voting threshold, then the candidate with the lowest number of votes is dropped and their votes are allocated to their 2nd choice, just as in the example above of instant runoff voting.

Suppose some candidates got more votes than they needed to win. In a typical election, a candidate only needs a majority so those “extra" votes have no real value. That's not the case with ranked choice voting. After all, those voters also had preferences for who they wanted in all the remaining offices.

Once a candidate reaches the vote threshold, any “extra" votes they received are redistributed to the next preferred candidate -- proportionately. It's done like this:

  • The number of extra votes is divided by the number of voters for that candidate.
  • The resulting fraction of a vote goes to each of those voters' 2nd choice candidates.

All of those fractions of a vote are then added together. When these votes are counted, more candidates may now have reached the voting threshold. If all of the offices have not yet been filled by qualifying candidates, then the next lowest vote-getting candidate is dropped and the votes redistributed once again.

This process continues until four candidates have achieved the threshold and been elected. 

While this type of instant runoff voting seems challenging, remember vote tallying is almost always done by machines.

Ranked Choice Voting vs. Instant Runoff Voting

Instant runoff voting is actually a type of ranked choice voting. In instant runoff voting, there is a single winner for an elected office, whereas ranked choice voting can also be used to choose multiple candidates for office.

States That Use Instant Runoff or Ranked Choice Voting

Fifteen states use instant runoff or ranked choice voting methods in local or state elections: California, Colorado, Florida, Indiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Mexico, Utah, and Wisconsin.

Three states use ranked choice voting ballots for military and absentee voters: Alabama, Arkansas, and South Carolina.

Alabama previously used to use a form of instant runoff voting called the contingent vote, where instead of the lowest vote-getter being dropped in each round, all but the top two candidates were dropped and their votes distributed between the top two candidates.

Instant Runoff Voting Pros and Cons

Pros to IRV

Political parties and states have chosen instant runoff voting as a strategy to address shortcomings in the current voting system in which the person with the most vote wins, even if that candidate receives far less than half of the votes.

This is the challenge legitimate third-party candidates pose to a primarily two-party system. A majority of voters in a community may vote conservative (Republican or Libertarian) or liberal (Democratic or Green), but by voting for the third-party candidate who best represents their views, they split the vote in such a way that the positions and candidates that they least support win the election.

The “majority" winner, then, does not represent the views of the majority. The elected official does not enjoy the support of the voters. Worse yet, the many voters whose views are not represented become disillusioned. They may stop voting in future elections, fearing that by voting for the candidate they really want, they will wind up with an elected official they really do not want.

Instant runoff or ranked choice voting ensures that voters' preferences win the day. It eliminates the problem of “wasted" votes because the voter's second choice or third choice will also be considered. It ensures that the winner of the election actually is the candidate with the greatest level of support.

Cons to IRV

The most commonly cited problem is the complexity of a ranked choice ballot. Some voters have problems with traditional ballots; the ranked choice ballot is even more challenging. When a city or state begins using a ranked choice ballot, there is usually an educational campaign to help voters understand how to vote.

If a voter finds the ballot confusing and chooses to vote for only one candidate, and then that candidate is dropped, their voting preferences can no longer be considered. Their vote will be “wasted."

With ranked choice voting, the candidate with the most absolute votes may not win, which could happen if that candidate did not get a majority of first and second place votes. That can feel wrong for some voters.

Interested in Bringing Ranked Choice Voting to Your State?

If your community is looking for strategies to improve voter engagement, increase voter turnout, and provide better support for elected officials, ranked choice voting may be an option to consider. Talk to a lawyer knowledgeable about the election law for advice and guidance.

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