On one half of the space, the Clinton fans looked organized and polished. They wore matching, glow-in-the-dark, blue t-shirts that read, "I'm fighting for her." They held battery-operated foam lights that shone brightly when the lights dimmed and doubled as noise-makers.
Sanders' fans had glow sticks, too, the kind that glow after being snapped. While many of his fans wore Bernie 2016 t-shirts, they were mismatched and different colors. His section also included several homemade signs.
Sanders stood proudly as his supports screamed "feel the Bern" and "We want Bernie."
"Six months ago, when I began my campaign for president of the United States of America and when we announced we were going to take on the political and economic establishment of this country, very few people knew who I was," he said as his supporters cheered. "Well, in the last six months, things have changed."
Sanders began his remarks by complementing the work of President Obama and calling out Republicans who he said "are suffering from a very serious illness. They suffer from amnesia. They forgot what the world looked like seven years ago."
Clinton later told the crowd she wasn't running for the third terms of either her husband or President Obama.
I'm running for my first term and I'm running as a proud Democrat," she said.
"Let's show him how we appreciate Vice President Joe Biden and all he's done for this country," she said.
The only candidate to mention the other Democrats by name was O'Malley, who asked Clinton and Sanders to stand with him on cracking down on gun manufacturers. Though the majority of polls find him in low single digits, he told his smaller group of supporters that he likes "the tough fights."
"We are fighting for something worth saving," said O'Malley. "The American Dream is worth saving. It is time to stand up. It is time to join the fight. I am in this to win this."
But undecided Iowa Democrats seemed few in the crowd, which was dominated by vocal supporters of the presidential candidates from around the country.
An earlier version of this story stated Debbie Wasserman Schultz spoke at the dinner. Andy McGuire, chair of the Iowa Democratic party, spoke at the dinner.