The fleet of Democratic White House hopefuls is not only shrinking in overall number but also on the debate stage.

Only five Democrats have qualified thus far for the Jan. 14 debate in Des Moines, Iowa: former Vice President Joe Biden; U.S. Sens. Bernie Sanders, Elizabeth Warren and Amy Klobuchar; and South Bend, Indiana, Mayor Pete Buttigieg.

To qualify for the January debate, candidates must secure 225,000 unique donors and earn 5% in four DNC-approved national polls or 7% in two DNC-approved early state polls.

Gabbard, Booker to skip upcoming December debate

Entrepreneur Andrew Yang and New Jersey Sen. Cory Booker have met the donor threshold, but neither has yet met the polling requirement, according to WHIO. Yang had met the requirement in one poll, but Booker has not met the requirement in any poll.

Booker and U.S. Rep. Tulsi Gabbard also did not participate in December’s Los Angeles debate.

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Five Democrats on stage is quite the reduction in number from the party’s first debates in 2019. Twenty Democrats took the stage over two nights, June 26-27, in Miami.

2019 November Democratic debate highlights

Ten Democrats were in Atlanta's November debate at Tyler Perry Studios.

Several of those Democrats in that first debate have dropped out in recent months: former U.S. Rep. Beto O'Rourke in October; U.S. Sen. Kamala Harris in December; and former Housing and Urban Development Secretary Julián Castro on Jan. 2.

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The January debate is being co-hosted by CNN and the Des Moines Register. This seventh Democratic debate will be held at Drake University.