Donald Trump Is Rallying in Iowa, But Why Is the State So Important?

With the Iowa caucuses set bring the first voting in the Democratic primary race, President Donald Trump is campaigning throughout the state.

Trump will hold a rally Thursday night at Drake University's Knapp Center in Des Moines at 7 p.m. Dozens of Trump officials and supporters will be in Iowa to energize voters, while Democrats campaign to secure votes in the state caucuses, according to The New York Times.

Trump won Iowa in his 2016 race against Hillary Clinton, but he lost to Texas Senator Ted Cruz in the Iowa caucuses. While Trump is not running unopposed, his re-election efforts are more focused on Democratic candidates than former congressman Joe Walsh or former Massachusetts Governor Bill Weld, who are challenging him for the GOP nomination.

"Our Caucus Day operation is just a preview of what is to come," Trump campaign manager Brad Parscale told the Times. "This will be the strongest, best funded and most organized presidential campaign in history. We are putting the Democrats on notice: Good luck trying to keep up with this formidable re-election machine."

In Iowa, Vermont Senator Bernie Sanders leads the other Democratic candidates with 22.3 percent of voters, according to a January 30 polling average from FiveThirtyEight. Former Vice President Joe Biden follows closely, at 21.8 percent. South Bend, Indiana, Mayor Pete Buttigieg and Senator Elizabeth Warren follow with 16.3 percent and 14 percent, respectively.

Iowa is one of only six caucus states, along with Nevada, Kansas, North Dakota, Wyoming and May. Local party members meet in each of Iowa's precincts to discuss and select the candidate they want to run for president. The caucuses determine the delegates that are sent to the party's national convention.

Both parties began scheduling the Iowa caucuses in the 1970s, and an early win can indicate who will receive the nomination. Since 2000, every Democratic candidate who won the Iowa caucuses became the nominee. Despite this trend among the Democrats, the last three Republican presidential candidates have not won in Iowa.

Results from the Iowa caucuses also indicate which issues and campaign tactics resonate with voters in Middle America. Many candidates drop out of the race or make changes to their campaign strategies after polling poorly in these caucuses. In 2016, Democrat Martin O'Malley and Republican Mike Huckabee suspended their campaigns after the caucuses.

Despite this presidential-race tradition, some have voiced reasons for changing which state is first to vote. In November, former Secretary of Housing and Urban Development and then-Democratic candidate Julián Castro criticized the party's decision to keep Iowa as the first state in the early voting.

"I actually believe that we do need to change the order of the states, because I don't believe that we're the same country that we were in 1972," he told NBC. "That's when Iowa first held its caucus first. By the time we have the next presidential election, in 2024, it'll have been 50 years since 1972. Our country has changed a lot in those 50 years."

Castro suspended his campaign in January.

President Donald Trump arrives to speak during the Republican Party of Iowa Annual Dinner at the Ron Pearson Center in West Des Moines on June 11, 2019. MANDEL NGAN/AFP/Getty