The Democratic race for a 2020 presidential nomination was in full swing at the Iowa State Fair, boasting a crowded field of nearly two dozen contenders.

Twenty-one of those contenders visited the Des Moines Register Political Soapbox at the Iowa State Fair in August. While the candidates were in town, shaking hands and eating corn dogs, the Register decided to do a little experiment. With so many candidates in the race, how many people can actually recall all their names?

Register reporters gave participants one minute to name as many Democratic candidates as they could. Several people worked alongside family members and friends.

The Register conducted the experiment while former Colorado Gov. John Hickenlooper was still in the race. Hickenlooper quit the campaign on Thursday.

On average, fairgoers could name only 7.5 candidates of the list of 24. The four candidates who participated named an average of 16.5 candidates.

Former Vice President Joe Biden was name-checked most often, followed by a tie between U.S. Sen. Bernie Sanders of Vermont and U.S. Sen. Elizabeth Warren of Massachusetts. All three are polling leaders.

Only two participants did not include the former vice president in their list.

The least-named candidate was Miramar, Florida, Mayor Wayne Messam. According to the Register's candidate visit tracker, Messam has only campaigned in Iowa once and that was in April.

Only tech entrepreneur Andrew Yang, a fellow candidate, remembered Messam in his count.

More: Iowa Poll in June: Most likely caucusgoers say there are too many Democratic candidates for president

Among the presidential candidates who agreed to take part in the experiment, Yang named the most. He named 23 candidates, forgetting only Montana Gov. Steve Bullock. Yang technically remembered former Housing Secretary Julián Castro right after his time was up (with a clue from one of Yang's staffers), but we gave it to him.

South Bend, Indiana, Mayor Pete Buttigieg and Colorado U.S. Sen. Michael Bennet tied for second. Each named 16 would-be Democratic presidents.

New York City Mayor Bill de Blasio named 11.

"I'm not going to get the rest in ten seconds," he conceded as his time ran short. "But there's a lot of good candidates, and in the end we're all going to be together."

But the winner of the "Name the Candidates" game, by far, was the Register's own chief politics reporter, Brianne Pfannenstiel, who did some studying up (and was not included in the 20). She named all two dozen candidates, in alphabetical order, in just 12 seconds.

Tim Webber contributed graphics to this report. Ian Richardson and Quintez Brown contributed reporting.

Katie Akin and Clare Ulmer are politics reporters for the Register. Reach Akin at kakin@registermedia.com, 515-284-8041, or on Twitter at @katie_akin. Reach Ulmer at culmer@registermedia.com or 515-284-8724.

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