Iowa caucuses

Democratic presidential candidate Hillary Clinton, accompanied by former President Bill Clinton and their daughter Chelsea Clinton, speaks at her caucus night rally at Drake University in Des Moines, Iowa, on Feb. 1, 2016.

Democratic presidential candidate Sen. Bernie Sanders, I-Vt., arrives at his caucus night party on Feb. 1, 2016, in Des Moines, Iowa.

Republican presidential candidate Donald Trump blows a kiss to the crowd after conceding defeat in the Iowa Caucus during his President Caucus Watch Party at the Sheraton Hotel on Feb. 1, 2016 in Des Moines, Iowa.

Republican presidential candidate Sen. Marco Rubio, R-Fla., smiles while speaking at a caucus night rally on Feb. 1, 2016 in Des Moines, Iowa.

Hillary Clinton supporter Blake Cooper Griffin, center, from Los Angeles, California, watches as results are displayed on a television during the caucus night event of Democratic presidential candidate Hillary Clinton in the Olmsted Center at Drake University on Feb. 1, 2016 in Des Moines, Iowa.

Republican presidential candidate Ben Carson greets supporters at his campaign’s caucus night rally on Feb. 1, 2016, in West Des Moines, Iowa.

Ballots are counted following the Republican party caucus in precinct 317 at Valley Church on Feb. 1, 2016 in West Des Moines, Iowa.

Kim Frederick of Houston, Texas, arrives for the caucus night event for Democratic presidential candidate Hillary Clinton in the Olmsted Center at Drake University on Feb. 1, 2016, in Des Moines, Iowa.

People embrace as Republican presidential candidate Sen. Ted Cruz (R-TX) is declared the winner at the caucus night gathering at the Iowa State Fairgrounds on Feb. 1, 2016 in Des Moines, Iowa.

Kassidy Reis, center, serves as a writing surface for her mother, Kerri Reis, and friend Rachel Reeg, as they participate in a caucus at Eleanor Roosevelt Middle School, in Dubuque, Iowa on Feb. 1, 2016.

Supporters of Democratic presidential candidate Hillary Clinton cheer during the Democratic party caucus in precinct 317 at Valley Church on Feb. 1, 2016, in West Des Moines, Iowa.

Josh Kent celebrates at the caucus night rally for Republican presidential candidate Sen. Ted Cruz, R-Texas, on Feb. 1, 2016, in Des Moines, Iowa.

Supporters watch as results are displayed on a television during the caucus night event of Democratic presidential candidate Hillary Clinton in the Olmsted Center at Drake University on Feb. 1, 2016, in Des Moines, Iowa.

Precinct secretary Michelle Anderson counts votes for Republican candidates during a caucus in Nevada, Iowa on Feb. 1, 2016.

Two voters hold up a sign for Republican presidential candidate Sen. Marco Rubio as presidential candidate Donald Trump, center, and wife, Melania, right, visit Saint Francis of Assisi Church, a caucus site, on Feb. 1, 2016, in West Des Moines, Iowa.

Barb Madden-Bittle, center, a supporter of Democratic presidential candidate Hillary Clinton, and Barb Royal, right, a supporter of Sen. Bernie Sanders (I-VT), try to persuade John Norwood, left, who is undecided, to caucus for their candidate during the Democratic party caucus in precinct 317 at Valley Church on Feb. 1, 2016 in West Des Moines, Iowa.

Supporters watch as results are displayed on a television during the caucus night event of Democratic presidential candidate Hillary Clinton in the Olmsted Center at Drake University on Feb. 1, 2016, in Des Moines, Iowa.

A caucus worker checks in a voter prior to the Republican Party caucus at Keokuk High School on Feb. 1, 2016, in Keokuk, Iowa.

Supporters wait for Republican presidential candidate Donald Trump at his caucus night rally on Feb. 1, 2016, in West Des Moines, Iowa.

People wait for caucus returns at the Donald Trump for President Caucus Watch Party at the Sheraton Hotel on Feb. 1, 2016, in Des Moines, Iowa.

Supporters watch the results as they wait for Republican presidential candidate Donald Trump at his caucus night rally on Feb. 1, 2016, in West Des Moines, Iowa.

Republican presidential candidate Sen. Marco Rubio, R-Fla., waits with his family to speak at a caucus site Feb. 1, 2016, in Clive, Iowa.

Republican presidential candidate Donald Trump, center, accompanied by his wife, Melania, second from right, pauses for a selfie while visiting St. Francis of Assisi Church, a caucus site, Feb. 1, 2016, in West Des Moines, Iowa.

Democratic presidential candidate Sen. Bernie Sanders, I-Vt., watches caucus returns in his hotel room, on Feb. 1, 2016, in Des Moines, Iowa.

Former President Bill Clinton hugs a volunteer who is working for his wife, Democrat Hillary Clinton, as he visits a campaign office on her behalf Feb. 1, 2016, in Ankeny, Iowa.

A supporter of Republican presidential candidate Sen. Marco Rubio, R-Fla., holds a sign up at a caucus site Feb. 1, 2016, in Clive, Iowa.

John Hathaway shows his hat, which has been signed by all the current presidential candidates, during a Jeb Bush campaign event in Des Moines, Iowa, on Feb. 1, 2016, ahead of the Iowa caucuses.

A supporter of Republican presidential candidate Jeb Bush holds up a placard as he speaks at a campaign event in Des Moines, Iowa, on Feb. 1, 2016, ahead of the Iowa caucuses.

Republican presidential candidate Ted Cruz campaigns at Greene County Community Center in Jefferson, Iowa on February 1, 2016.

Democratic presidential candidate Hillary Clinton takes photos with workers at her campaign office in Des Moines, Iowa, on Feb. 1, 2016.

A cookie in the shape of Democratic presidential candidate Sen. Bernie Sanders, I-Vt., sits on a desk during a visit to campaign headquarters to thank volunteers, on Feb. 1, 2016, in Des Moines, Iowa.

A volunteer makes calls to potential Rand Paul voters at his Des Moines headquarters on February 1, 2016 in Des Moines, Iowa.

Republican presidential candidate, New Jersey Gov. Chris Christie, signs a hat for Jon Hathaway after a luncheon at the Bull Moose Club February 1, 2016 in downtown Des Moines, Iowa.

Senator Rand Paul (R-TX) poses for photos with volunteers after speaking during a caucus day rally at his Des Moines headquarters on February 1, 2016 in Des Moines, Iowa. The Presidential hopeful was accompanied by his wife, Kelly, mother, Carol Wells and his father, former Congressman Ron Paul. Pauls were there to thank all the staff and volunteers for all their hard work in Iowa.

Democratic presidential candidate Bernie Sanders visits his campaign headquarters to thank volunteers on Feb. 1, 2016, in Des Moines, Iowa.

Republican presidential candidate Jeb Bush shakes hands with a supporter at a Des Moines, Iowa, campaign event on Feb. 1, 2016, ahead of the Iowa caucuses.

Republican presidential candidate Jeb Bush points out a scar on his forehead to supporters as he speaks at a campaign event in Des Moines, Iowa, on Feb. 1, 2016, ahead of the Iowa caucuses.

Volunteer Holly Fussett, right, of Washington, DC, participates in phone banking at Democratic presidential candidate Sen. Bernie Sanders (I-VT) campaign headquarters on Feb. 1, 2016, in Des Moines, Iowa. Residents of Iowa will vote for the Republican and Democratic nominees at the caucuses this evening.

Republican presidential candidate Ted Cruz carries his daughter Caroline, 7, as he arrives at the Green County Community Center for a campaign event on Feb. 1, 2016, in Jefferson, Iowa.

Buttons are displayed at the Green County Community Center before Republican presidential candidate Ted Cruz arrives for a campaign event on Feb. 1, 2016, in Jefferson, Iowa.

A supporter of Republican presidential candidate Rand Paul campaigns for him on a busy street corner in Des Moines, Iowa, during morning rush hour on Feb. 1, 2016.

Republican presidential candidate Donald Trump is greeted by his wife, Melania Trump, at a campaign rally at the Ramada Waterloo Hotel and Convention Center on Feb. 1, 2016, in Waterloo, Iowa.

A woman takes a selfie as Republican presidential candidate Donald Trump greets audience members following a campaign rally at the Ramada Waterloo Hotel and Convention Center on Feb. 1, 2016 in Waterloo, Iowa.

Supporters of Democratic presidential candidate Martin O’Malley campaign for their candidate on a busy street corner during morning rush hour on Feb. 1, 2016, in Des Moines, Iowa.

Republican presidential candidate Ted Cruz talks to supporters after a campaign event at the Iowa State Fairgrounds on Feb. 1, 2016, in Des Moines, Iowa.

Republican presidential candidate Ted Cruz speaks to supporters at the Green County Community Center on Feb. 1, 2016, in Jefferson, Iowa.