On Feb. 1, Iowa voters will gather in select caucus sites to choose their respective national parties’ presidential candidates. However, for the first time in the history of the Iowa Caucus process, active duty members of the military and civilians living abroad will be allowed to participate and cast their vote. The Iowa Caucus has served as the first major electoral event of the U.S. presidential nominating process since 1972. Both the state Republican and Democratic Iowa parties administer their own set of caucuses that are subject to their own set of rules that can change from time to time (e.g., voters in each party's caucus must be registered with that party, voters can change their registration at the caucus location, etc.).