Photos: 2020 Iowa caucuses

Bernie Sanders, with wife Jane O’Meara Sanders, greets supporters at a caucus night rally in Des Moines.  (Pablo Martinez Monsivais / Associated Press)

Elizabeth Warren hugs her grandchildren Atticus Mann Tyagi and Lavinia Tyagi before addressing supporters in Des Moines.  (Chip Somodevilla / Getty Images)

Joe Biden with his wife, Jill Biden, at a caucus night rally in Des Moines.  (Marcio Jose Sanchez / Associated Press)

Amy Klobuchar greets supporters at her caucus night rally in Des Moines.  (Nati Harnik / Associated Press)

Troy Price, chairman of the Iowa Democratic Party, is surrounded by reporters after speaking about the technical issues that delayed the caucus results in Des Moines.  (Joshua Lott/AFP )

Bernie Sanders supporters await results at a caucus watch party in Des Moines.  (Kerem Yucel / AFP/Getty Images )

Observer David Soll of Rockford, Ill., talks to participants during the Democratic caucus at the Tri-State Independent Blind Society in Dubuque, Iowa.   (Dave Kettering / Telegraph Herald)

A supporter for Andrew Yang waits before a Democratic caucus at Hoover High School in Des Moines.   (Charlie Neibergall / Associated Press)

Caucusgoers check in at Hoover High School in Des Moines.   (Charlie Neibergall / Associated Press)

A caucus gathering at Abraham Lincoln High School in Des Moines.  (Jim Watson / AFP/Getty Images )

People caucusing for Pete Buttigieg begin to fill his section of the Knapp Center at Drake University in Des Moines.  (Gene J. Puskar / Associated Press)

On caucus night in Iowa, Bernie Sanders supporters attend a caucus watch party in Washington, D.C.   (Mario Tama / Getty Images)

Bernie Sanders supporters at their caucus precinct at Abraham Lincoln High School in Des Moines.  (Jim Watson / AFP/Getty Images)

Joanne Smith of Chicago attends a Joe Biden rally in Des Moines.  (Marcio Jose Sanchez / Associated Press)

Bernie Sanders supporters wait before a caucus night rally for their candidate in Des Moines.  (Kerem Yucel / AFP/Getty Images )

Caucusgoers aligned with Joe Biden hold up their first votes at the Knapp Center at Drake University in Des Moines.  (Gene J. Puskar / Associated Press)

Caucusgoers at Roosevelt High School in Des Moines.   (Andrew Harnik / Associated Press)

Pete Buttigieg supporters gather at a caucus site at Roosevelt High School in Des Moines.  (Andrew Harnik / Associated Press)

Caucusgoers at Roosevelt High in Des Moines.   (Andrew Harnik / Associated Press)

A line at a Democratic caucus site at Hoover High School in Des Moines.   (Charlie Neibergall / Associated Press)

Elizabeth Warren speaks Monday at Roosevelt High School, a caucus site in Des Moines.   (Andrew Harnik / Associated Press)

Volunteers prepare an area in the Roosevelt High School gymnasium in Des Moines where supporters of Pete Buttigieg will rally while caucusing.   (Chip Somodevilla / Getty Images)

Bernie Sanders precinct captain Clara Gilbert indicates the area where Sanders supporters should gather during the first alignment of caucusgoers at the Cedar Rapids Public Library.  (Jim Slosiarek / Gazette)

Amy Pfeiffer prepares a flag in advance of a Buttigieg caucus night watch party at Drake University Bell Center in Des Moines.  (Gary He / European Pressphoto Agency )

Volunteers prepare an area of the Roosevelt High School gym in Des Moines where Elizabeth Warren supporter will rally during caucusing.   (Chip Somodevilla / Getty Images)

Workers prepare the stage for Amy Klobuchar’s caucus night rally at the Marriott hotel in Des Moines.   (Scott Olson / Getty Images)

Joe Robinson vacuums before a caucus night gathering for Bernie Sanders at the Holiday Inn in Des Moines.   (Joe Raedle /Getty Images)

Democratic presidential candidate Joe Biden speaks at a campaign stop at Hiatt Middle School in Des Moines.   (Andrew Harnik / Associated Press)

Democratic presidential candidate Pete Buttigieg speaks at Lincoln High School during a Get Out the Caucus rally in Des Moines.   (Win McNamee / Getty Images)

Democratic presidential candidate Tom Steyer makes a stop at Backpocket Brewing in Coralville, Iowa.  (Joseph Cress / Associated Press)

Pete Buttigieg casts a shadow on the Iowa state flag as he speaks at a campaign event at Northwest Junior High in Coralville, Iowa.   (Matt Rourke / Associated Press)

Supporters wait for the arrival of Joe Biden during a campaign event in Dubuque, Iowa.   (Marcio Jose Sanchez / Associated Press)

Democratic presidential candidate Bernie Sanders with his wife, Jane O’Meara Sanders, speaks to supporters in Des Moines.  (John Locher / Associated Press)