Iowa is one of the few states that runs a caucus rather than a primary for Presidential Elections. What is a caucus? That is a great question! Here is your resource to understanding the caucus and how to participate during Presidential Election cycles.
A caucus is a local meeting that is financed and managed by the two major political parties (Democrat and Republican). At the caucus, registered party members (you cannot be registered undecided, you must register within a specific party) come together to discuss and express support for their candidate. Each party runs the caucus a little differently. In the most recent caucus, Republicans case a secret ballot for their preferred candidate while Democrats physically grouped themselves around the room based on the candidate they support. It is important to note that participants are not picking the candidate themselves but rather choosing delegates who will represent their vote at the next convention level.
Read chapter three of Why Iowa? How Caucuses and Sequential Elections Improve the Presidential Nominating Process by David P. Redlawsk, Caroline J. Tolber, and Todd Donovan. This chapter provides more information on the rules of a caucus in Iowa, the history of the Iowa caucus, and the purpose of the caucus.
The Council on Foreign Relations provided the information on this page regarding a caucus. Visit the Council on Foreign Relations website to learn more. The Washington Post also provides some useful information on a caucus, based on the 2016 Presidential Election.