After months of campaigning and debating, the 2016 presidential candidates will be put to their first test as Iowans head to the caucuses Monday night.

“The Iowa caucuses are important because there has been such a lead-up to it,” James Henson, Director of the Texas Politics Project at the University of Texas in Austin said. “Iowa is the first of the primary contests, and so the real game here is expectations.”

Iowa voters are the first to cast their votes on whom they think should be the next American president, setting the tone for this election season. Henson said Iowa is one of the few states to hold a “caucus” instead of a primary, which means voters in the state must physically show up to a venue to support the candidate of their choice.

Democrats and Republicans caucus differently. During the Republican caucus meetings, Iowan voters will write down their presidential pick on a piece of paper or a ballot. The votes are tallied up by local party officials at each venue and sent to Iowa GOP headquarters.

The Democratic caucus system is more public. At the start of the caucus meetings, voters must openly declare a preference for a candidate. Throughout the meeting, the voters interact with each other; voters have the opportunity to convince other voters to come join them in standing for their favorite candidate.

“The main difference between the Democratic and the Republican caucuses is that in the Democratic caucus in Iowa you have a process in which voters that are aligned with candidates that aren’t meeting a minimum threshold wind up having to be subdivided among the top candidates that meet the threshold,” Henson said. “The thing to really understand is that it the caucuses are a much more public and social way of people gathering and registering their preferences in a party function than we see in state with primaries.”

According to the latest Iowa poll released Monday morning, Donald Trump was the Republican front-runner ahead of Texas Senator Ted Cruz, and Vermont Senator Bernie Sanders was in the lead for the Democrats.

“In the run up to the Iowa caucuses we’ve been looking at polls; we’ve been looking at the size of crowds,” Henson said, “None of that counts in the nomination process.”

Henson said after Iowa, the next big state for the candidates to win over is Texas.

“Texas has something like more than four times as many delegates as Iowa,” Henson said. “So, by the time we get to Texas on March 1st, a lot of eyes will be on Texas and there will be a lot of money just like we are seeing in Iowa right now, we’ll see a lot of candidate activity and a whole lot of ads.”

Texans will cast their primary votes on March 1st, also known as Super Tuesday. The deadline to register to vote during the March primary election in Texas is February 1st. Click here to register.