How the Iowa Caucus Works: Significance of the Iowa Caucus

The Iowa Caucus is an electoral event that has been held every other year in Iowa since 1972. Both the Democratic Party and Republican Party hold Iowa caucuses for the midterm and general elections. The caucuses for presidential elections attract the most national attention because they’re the first significant event in the presidential election cycle, usually occurring in January or February.

Due to its placement in the cycle, Iowa is often considered a strong indicator of how a presidential candidate will do during the entire campaign process. Candidates who fare poorly in Iowa will often drop out of the race, though this is not always the case. When Joe Biden ran for president in 2020, he ended the Iowa caucus with the support of around 15 percent of the Iowa Democratic Party, far behind nominees like Mayor Pete Buttigieg and Senator Bernie Sanders at 26 percent. Former President Donald Trump, who was running for reelection that year, earned 97 percent support from the GOP state party.

Iowa is the first caucus because the Democrats realigned each state's nomination schedule in the early 1970s after protests disrupted the 1968 Democratic Convention in Chicago, Illinois. For the 1972 convention, Democrats decided to spread out the nominations throughout the year. Due to its complicated caucuses, Iowa moved their nomination from late March to late January, which made them the first contest on the election circuit.

The Iowa caucus is significant because it is the first event in the presidential election cycle. After Jimmy Carter became the first Democrat to win both the Iowa caucus and the White House in 1976, the caucus became a bellwether for a candidate's success. Since then, the Iowa caucus results have only shown moderate success in picking the presidential election, choosing only 55 percent of Democratic winners and 43 percent of Republican winners. One of the few exceptions to these results occurred in 2008, when former president Barack Obama, an underdog at the time, won the Iowa caucus, the Democratic nomination, and the presidency.

The Iowa caucuses’ popularity has waned in recent years. Some elected officials, political experts, and voters have called for an end to the state’s first-in-the-nation status. Some consider the caucus to be dated and more complicated and expensive than primaries, which only require a single vote. Critics have also cited the fact that their in-person requirement can exclude many potential voters, including the elderly, ill, and night shift workers.

In 2020, the results were delayed because of problems with a mobile app supposed to help with the vote count. A partial recount declared Mayor Pete Buttigieg the winner with 26.2% of the vote and nine delegates. Buttigieg later placed second after Joe Biden in the New Hampshire primary and dropped out of the race after ranking fourth in the South Carolina primary.

The Iowa caucuses work differently for both parties. Republicans simply pick a candidate with a ballot vote, but the Iowa Democratic Party follows this structure:

1. 1. First alignment. At the caucus site, Iowans split into preference groups according to their chosen candidate or if they are undecided. Members of each preference group can try to convince other groups to join their ranks, while the undecided group can ask questions about each group's candidate.
2. 2. First count. Caucus organizers will count the total number of caucus-goers at their precinct. The candidate whose group meets or surpasses the viability threshold—usually 15 percent of the attendees—is considered viable to win the precinct vote and has the potential to add their delegates to their total.
3. 3. Second alignment. Following the first round, attendees whose candidates did not clear the viability threshold can then participate in a realignment. This process allows them to either join another candidate's group, convince voters from another non-viable candidate's group to join them, or abstain from realignment.
4. 4. Second vote. A second and final vote is taken on caucus night. Every candidate that clears the viability threshold receives at least one delegate—a mathematical equation determines how many delegates each candidate is given. The results of each precinct's alignments and delegates are then reported to the state party, which totals the number of delegates awarded at each precinct and declares a winner of the Iowa Democratic Caucus. The winning candidate's delegates are later sent to the county convention, which picks the state delegate equivalents for the district and state conventions.

Caucuses are very different from primary elections, which occur in the same way as a general election, with members of both parties voting on a secret ballot at polling places. Iowa Democrats and Republicans instead gather in precinct caucuses in locations like schools, libraries, or even residences in one of the state's 1,678 voting precincts or its 99 satellite locations across the United States and abroad.

Voters at these precinct caucuses will debate over their preferred candidate and eventually elect delegates to send to their county conventions. This vote is the beginning of a process that will ultimately send 41 convention delegates, also known as state delegate equivalents, to represent Iowa at the respective party's national conventions. Caucus-goers will even begin to outline their parties' platforms by introducing resolutions.

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