CEDAR RAPIDS, Ia. — It was a chaotic scene at the DoubleTree Hilton Hotel and Convention Center in downtown Cedar Rapids on Sunday, as 19 presidential candidates converged for the state’s largest caucus event so far this cycle.

Many of the campaigns and their supporters arrived early in the morning to line the street to the hotel, chanting and hoisting signs.

Fans of Sen. Amy Klobuchar, D-Minnesota, chanted, “Midwest is best!” as they awaited her arrival, and she yelled into a bullhorn that President Donald Trump has used Iowa farmers “like poker chips” in his trade negotiations.

Down the street, former U.S. Rep. John Delaney, D-Maryland, enlisted a bagpiper, but the notes were eventually drowned out as Sen. Cory Booker, D-New Jersey, arrived and stepped into the bed of a pickup truck to tell his people that they are "Donald Trump’s worst nightmare.”

“This is an organizing test,” Booker said. “And I’m telling you, we’re going to march all the way to caucuses, and on that night, when we win, it won’t be a win for one person. When we win, it will be a win for America.”

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As Booker wrapped up, Sen. Bernie Sanders, I-Vermont, led a large group of protesters down the road to the hotel holding signs and rallying for a $15 minimum wage. He helped hold a yellow and red banner that said, "Unions for All."

He had spoken earlier in the afternoon at a Fight for $15 rally outside a Cedar Rapids McDonald’s, where he called on the chain to raise its starting wage to $15 and negotiate with a workers union.

“Today, we say as loudly and clearly as we can to McDonald's: Pay your workers a living wage,” he said. “The fight at McDonald's is the fight of millions of working-class people who are sick and tired of working longer hours for lower wages.”

A few blocks from the Hall of Fame event, Carrie Ball, a 47-year-old stay-at-home mom from Cedar Rapids, was sitting on the grass at a picnic with candidate Pete Buttigieg, where the South Bend, Indiana, mayor played a game of bags and talked with supporters.

Ball, a self-described “political junkie,” said she loved that so many candidates were in town. She said she really likes Buttigieg, but she also really likes Sens. Elizabeth Warren, D-Massachusetts, and Kamala Harris, D-California.

Harris flew to Iowa just hours after giving a speech at a major NAACP event Saturday in South Carolina. Harris entered the Cedar Rapids venue and immediately went into a room to address her supporters. The group had been outside of the venue for hours, cheering for the former prosecutor. The group was among the largest outside the venue.

Harris thanked her supporters and indicated she would visit them — and Iowa — often.

“I fully intend to win this election,” she said to cheers.

Warren arrived to supporters who chanted, “L-I-Z Warren’s got a plan for me!”

Warren shook hands with the group, doled out hugs and stopped to answer questions from reporters.

“One of the best parts about Cedar Rapids is how many people are engaged — that they understand that 2020 is a huge moment for our country and that what happens will mark us for generations to come. It’s going to come right through the heart of Iowa, and that means it’s going to come right through the heart of Cedar Rapids.”