Democratic presidential candidate Sen. Elizabeth Warren at the Polk County Democrats' Steak Fry in Des Moines, Iowa, Saturday.

The event coincided with 2020 candidate Sen. Elizabeth Warren emerging as the Democratic front-runner in Iowa in a new poll. Photo: Scott Olson/Getty Images

Democratic presidential candidate, former Vice President Joe Biden works the grill at the Polk County Democrats' Steak Fry on September 21

Democratic presidential candidate Joe Biden works the grill at the Water Works Park event. Photo: Scott Olson/Getty Images

Democratic presidential candidate, U.S. Sen. Kamala Harris (D-CA) dances as she attends the Democratic Polk County Steak Fry on September 21, 2019 in Des Moines, Iowa.

2020 hopeful Sen. Kamala Harris dances with supporters in Des Moines. Photo: Joshua Lott/Getty Images

Democratic presidential candidate and South Bend, Indiana mayor Pete Buttigieg greets supporters at the Polk County Democrats' Steak Fry on September 21, 2019 in Des Moines, Iowa.

Democratic presidential candidate and South Bend, Indiana, Mayor Pete Buttigieg with his supporters. Photo: Scott Olson/Getty Images

Democratic presidential candidate, Sen. Cory Booker (D-NJ) takes a selfie during the Democratic Polk County Steak Fry on September 21, 2019 in Des Moines, Iowa.

2020 candidate Sen. Cory Booker takes a selfie. Photo: Joshua Lott/Getty Images

Democratic presidential candidate, U.S. Sen. Bernie Sanders (I-VT) speaks during the Democratic Polk County Steak Fry on September 21, 2019 in Des Moines, Iowa.

Democratic presidential candidate Sen. Bernie Sanders addresses the crowd. Photo: Joshua Lott/Getty Images

Democratic presidential candidate, Sen. Amy Klobuchar (D-MN) marches with supporters at the Polk County Democrats' Steak Fry on September 21, 2019 in Des Moines, Iowa.

2020 candidate Sen. Amy Klobuchar marches with supporters. Photo: Scott Olson/Getty Images

Democratic presidential candidate, former Rep. Beto O’Rourke (D-TX) greets an attendee during the Democratic Polk County Steak Fry on September 21, 2019 in Des Moines, Iowa.

Democratic presidential candidate Beto O’Rourke greets an event attendee. Photo: Joshua Lott/Getty Images

Democratic presidential candidate Rep. Tulsi Gabbard (D-HI) works the grill during a visit to the Polk County Democrats Steak Fry on September 21, 2019 in Des Moines, Iowa.

2020 candidate Rep. Tulsi Gabbard works the grill. Photo: Scott Olson/Getty Images

Democratic presidential candidate, entrepreneur Andrew Yang greets guests at the Polk County Democrats' Steak Fry on September 21, 2019 in Des Moines, Iowa.

Democratic presidential hopeful Andrew Yang greets event attendees. Photo: Scott Olson/Getty Images

Attendees listen to Democratic presidential candidate, Rep. Tim Ryan (D-OH) speak during the Democratic Polk County Steak Fry on September 21, 2019 in Des Moines, Iowa

Attendees listen to 2020 candidate Rep. Tim Ryan speak. Photo: Joshua Lott/Getty Images

An attendee puts syrup of a stack of pancakes during the Democratic Polk County Steak Fry

An attendee puts syrup of a stack of pancakes. Photo: Joshua Lott/Getty Images

Democratic presidential campaign signs are displayed during the Democratic Polk County Steak Fry on September 21, 2019 in Des Moines, Iowa.

Democratic presidential campaign signs are displayed during the event. Photo: Joshua Lott/Getty Images

In photos: 2020 Democratic candidates flock to Iowa steak fry

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