Iowa is the first big vote in the whole state to choose who the Republican candidate will be for the 2024 US presidential election.
The caucus voting begins at 7:00 PM in the evening in different places around the state like schools, churches, and small events. This is 8:00 PM Eastern time and 1:00 AM Greenwich Mean Time.
Voters will have to deal with very cold temperatures of -23C (-9F) because of winter storms that covered the state with snow and ice.
According to the latest poll, 48% of Iowa voters prefer Donald Trump, while Nikki Haley (20%) and Ron DeSantis (16%) are his closest competitors.
Haley or DeSantis doing very well in second place could help them a lot in the race to choose a candidate for the election in November.