How The Iowa Caucuses Work — And Why They’re Important

Iowa Democrats gather Monday to kick off the nominating contests that will pick the party’s presidential nominee — the person who will take on President Trump in November.

But how they do it is complicated.

The Iowa caucuses are kind of like neighborhood meetings where people get together and — out in the open, with no secret ballot — try to win over their friends, family and neighbors to support their preferred candidate.

The caucuses start a months-long process that eventually leads to the selection of 41 delegates, who will vote for a candidate at the party’s national convention. It’s a complex, unique and exhausting process that might go a little differently if done in a place that was temperamentally unlike Iowa.

The caucuses quadrennially come under fire for being overwhelmingly white and not representative of the country, let alone the Democratic Party. But the candidates have spent millions there and over the last 40 years, and it’s been very predictive of who becomes the Democratic nominee.

Let’s break down how all this works.

What time do the caucuses take place?

They begin at 7 p.m. CT (8 p.m. ET) and are expected to last roughly an hour. The Iowa Democratic Party is trying to expedite the process this year with just two rounds of caucusing, so they may very well be wrapped up in less than an hour.

Who can vote?

The caucuses are “open.” In other words, any registered voter in the state can participate.

But for as much attention as the caucuses get, not many Iowans actually participate. In 2016, for example, less than 16% of people eligible to vote actually caucused.

And that was the second-highest turnout in the history of the Iowa Democratic caucuses, at more than 171,000 people. The record was 239,000 in 2008.

For what it’s worth, given the record number of candidates this year, the Iowa Democratic Party is anticipating a record-breaking turnout.

Where do the caucuses happen?

They happen all around the state’s 99 counties at 1,678 precinct locations, including in people’s homes, public libraries and school gymnasiums.

How will we know who wins?

This year will be extra confusing, because the state party will release three different results:

  1. the statewide preference after the first alignment;
  2. the preference after the second alignment;
  3. and the final “State Delegate Equivalents,” or SDEs.

SDEs are the estimated number of delegates each candidate would get to the congressional district and state conventions.

Various campaigns will use the potentially differing results to their advantage, but delegates are the name of the game in Iowa. That’s why the campaigns have built up operations with hundreds of staffers and volunteers in the state, to show their grassroots support and campaign strength of organization.

So while the first two results will be useful to inform analyses, the “winner” will be who gets the most SDEs.

How are the delegates selected?

The caucusgoers from the 1,678 precincts determine 11,402 delegates, who will go to county conventions on March 21.

They are then filtered to a smaller universe of delegates who go to the congressional district conventions April 25, the state convention June 13 and then, finally, just 41 delegates who get to go to the national convention July 13-16 in Milwaukee, Wis.

To hold onto delegates, campaigns have to try and keep activists and staffers at each of these steps because they are not bound to their candidates, and often the results can be very different from the caucus night results.

For example, on the Republican side in 2012, Ron Paul’s band of activists gamed the system, stuck around for each step, wound up with the most delegates out of Iowa in the end (despite losing on caucus night), and took over the Iowa GOP.

How do the caucuses themselves work?

There are two rounds of caucusing, and candidates need to get at least 15% of the assembled crowd in order to receive any delegates.

If a candidate does not get 15%, they get no delegates, and their voters can re-sort and go to their second choice in the next — and final — round.

Once the re-sorting is finished, the number of people in each candidate’s corner is tallied and submitted using a complicated worksheet to figure out the number of delegates that would be assigned.

So if a candidate doesn’t get 15% in the first round, he or she is eliminated?

Pretty much. That’s why candidates who have been polling far below that threshold have little chance of picking up any delegates.

It’s also worth noting that there is a 15% threshold to pick up delegates in every Democratic nominating contest in every state. This is a longstanding Democratic National Committee rule to avoid lots of candidates splitting the vote and creating brokered conventions.

Are there any exceptions?

There is one caveat in Iowa. Someone who doesn’t get enough support in the first round has a chance to move into the final round if they can convince enough supporters of other nonviable candidates to lend them their votes for the second round.

Here’s an example: Say 100 people caucus, and in the first alignment, 25 go for Bernie Sanders, 22 for Joe Biden, 17 for Pete Buttigieg, 14 for Elizabeth Warren, 10 for Amy Klobuchar, nine for Andrew Yang and three for Tom Steyer.

Sanders’, Biden’s and Buttigieg’s support is locked in. Their numbers can’t decline in the next round. If Warren’s team convinces one Klobuchar, Yang or Steyer first-round supporter to go with her, she’d be viable and would get some delegates. In theory, if Warren’s supporters convinced, say, all of Klobuchar’s, Yang’s and Steyer’s backers to go with her, Warren would actually win the most delegates from the caucus site. The odds of that are not very good, but the “Zombie Candidate” is, in theory, possible.

Is there any check on the number of caucusgoers tallied?

Yes. For the first time this year, caucusgoers will write down who they are supporting so there will be paper backups, in case recounts are necessary.

There was no way to do a recount in previous years, and that became a problem in some caucus locations in 2016 because at least a dozen precincts were decided by coin flip between Sanders and Hillary Clinton.

What about “superdelegates”?

There are eight unpledged delegates in Iowa who bypass this whole process and go straight to the national convention. They are officially called “automatic delegates” now.

They used to be colloquially called “superdelegates.” That was never their official name, but the media would call them that and members of the DNC would use it, too, because these current and former party leaders’ and elected officials’ “super” power used to be that they were able to vote however they wanted at the convention.

They could tip the scales of a campaign for their preferred candidate, although most went with the direction the political wind was blowing and backed the candidate ahead in the delegate race.

Still, as a result of the 2016 election, when so many came out early for Clinton, the party listened to the protests of the Sanders campaign and supporters and stripped superdelegates of their ability to vote on the first ballot at the national convention (unless there is already an overwhelming majority of delegates for one candidate).

Does Iowa have a big number of delegates at stake?

Not really. Iowa only has 41 pledged delegates to the national convention, and, as noted, it takes months to pick them. Those 41 delegates account for just 1% of all pledged delegates. (A candidate needs at least 1,991 delegates to become the nominee.)

Iowa and New Hampshire combined have just 2% of the delegates, and the first four states, including Nevada and South Carolina, have just 5%.

Then why are they so important?

The real impact of these early contests is momentum — who does well, who doesn’t and who beats expectations will determine who continues to see a viable path for themselves to the nomination.

And Iowa in particular is important for the Democratic nomination. The last seven of nine people who have won Iowa have gone on to be the nominee, including the last four.

It’s all why — despite the caucuses being more than 90% white — as of two weeks ago, the candidates had spent $50 million on ads in Iowa alone.

Copyright 2020 NPR. To see more, visit