Six of the Democratic Party’s 12-person presidential field are set to debate in Iowa at 9 p.m. Eastern time on Tuesday.

Six Democratic presidential hopefuls are preparing to square off Tuesday night in Des Moines, Iowa, in the first debate of the year, but the 2020 field is still a dozen strong with the primary season set to begin.

Twelve Democrats are vying for the party’s nomination, with the Iowa caucuses less than a month away. The field shrank by one on Monday as Sen. Cory Booker suspended his campaign, saying he didn’t have the money to build a winning operation. His exit followed author Marianne Williamson, who dropped out on Friday.

Former Vice President Joe Biden continues to lead the pack in national polls, though Sen. Bernie Sanders and ex–South Bend, Ind., Mayor Pete Buttigieg outrank him in surveys focused on Iowa, which has a critical role thanks to its first-in-the-nation caucuses. Sen. Elizabeth Warren has dropped to fourth in the Iowa polling, and she also has lost ground in national polling, giving up the No. 2 spot to Sanders. Late Friday, Sanders scored the top spot in a new Des Moines Register/CNN/Mediacom Iowa poll.

The Democratic Party’s pool of White House hopefuls has contracted from its original size of more than two dozen, but other contenders have made late entries. Billionaire former New York City Mayor Michael Bloomberg formally launched his campaign on Nov. 24, former Massachusetts Gov. Deval Patrick entered on Nov. 14, and billionaire investor Tom Steyer announced his run in July.

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Steyer last week became the sixth candidate to qualify for Tuesday night’s debate, where he will join Biden, Buttigieg, Sen. Amy Klobuchar, Sanders and Warren on stage.

The other Democrats seeking to take on President Donald Trump in November include entrepreneur Andrew Yang, Sen. Michael Bennet of Colorado and Rep. Tulsi Gabbard of Hawaii.

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After the Iowa caucuses, The Democrats’ focus will shift to the New Hampshire primary and beyond, as candidates aim to pick up the 1,885 delegates to secure the Democratic Party’s nomination.

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Here is the MarketWatch list of contenders and the status of their candidacies, based on their statements:

Name Age State of candidacy
Former Georgia gubernatorial candidate Stacey Abrams 46 Said Aug. 13 that she’s not running for president.
Sen. Michael Bennet of Colorado 55 Running for president.
Former Vice President Joe Biden 77 Running for president.
Former New York City Mayor Michael Bloomberg 77 Running for president.
Sen. Cory Booker of New Jersey 50 Was running for president, dropped out Jan. 13.
Montana Gov. Steve Bullock 53 Was running for president, dropped out Dec. 2.
Former South Bend, Ind., Mayor Pete Buttigieg 37 Running for president.
Ex–HUD Secretary Julián Castro 45 Was running for president, dropped out Jan. 2.
New York City Mayor Bill de Blasio 58 Was running for president, dropped out Sept. 20.
Former Rep. John Delaney of Maryland 56 Running for president.
Rep. Tulsi Gabbard of Hawaii 38 Running for president.
Sen. Kirsten Gillibrand of New York 53 Was running for president, dropped out Aug. 28.
Former Alaska Sen. Mike Gravel 89 Was running for president, dropped out Aug. 6.
Sen. Kamala Harris of California 55 Was running for president, dropped out Dec. 3.
Former Colorado Gov. John Hickenlooper 67 Was running for president, dropped out Aug. 15.
Washington Gov. Jay Inslee 68 Was running for president, dropped out Aug. 21.
Sen. Amy Klobuchar of Minnesota 59 Running for president.
Miramar, Fla., Mayor Wayne Messam 45 Was running for president, dropped out Nov. 29.
Rep. Seth Moulton of Massachusetts 41 Was running for president, dropped out Aug. 23.
Former Rep. Beto O’Rourke of Texas 47 Was running for president, dropped out Nov. 1.
Former Massachusetts Gov. Deval Patrick 63 Running for president.
Rep. Tim Ryan of Ohio 46 Was running for president, dropped out Oct. 24.
Sen. Bernie Sanders of Vermont 78 Running for president.
Former Rep. Joe Sestak of Pennsylvania 68 Was running for president, dropped out Dec. 1.
Tom Steyer, billionaire investor and activist 62 Running for president.
Rep. Eric Swalwell of California 39 Was running for president, dropped out July 8.
Sen. Elizabeth Warren of Massachusetts 70 Running for president.
Marianne Williamson, author and activist 67 Was running for president, dropped out Jan. 10.
Andrew Yang, founder of Venture for America 44 Running for president.