Rep. Tulsi Gabbard is the tenth candidate to qualify for the next Democratic presidential debate. It means that despite tougher criteria to qualify for the Nov. 20 contest, the field of those reaching the stage is not decreasing much.

Gabbard gained 3% approval in her fourth national or early-state poll Wednesday, according to tracking by Politico.

The requirements to qualify have steadily increased since the first debate in an effort to whittle down the field. It went from 20 in June and July to 10 in September to 12 in October.

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Candidates must have at least 165,000 unique donors to qualify for the November debate. They also must receive either 3% or more support in at least four national or early-state polls — or receive 5% or more support in two early-state polls. 

With one week left until the Nov. 13 deadline to qualify, here is who will be on the stage.

  • Former Vice President Joe Biden
  • Sen. Cory Booker
  • Mayor Pete Buttigieg
  • Rep. Tulsi Gabbard
  • Sen. Kamala Harris
  • Sen. Amy Klobuchar
  • Sen. Bernie Sanders
  • Billionaire Tom Steyer
  • Sen. Elizabeth Warren
  • Entrepreneur Andrew Yang

Everyone who has qualified is among the 12 who participated in the October debate. The other two were former Housing and Urban Development Julian Castro and former Rep. Beto O'Rourke.

Castro is still in the race after reaching a self-imposed goal of raising $800,000 by the end of October. But with one week until the debate deadline, he has not reached the qualifying mark in any required polls.

O'Rourke ended his campaign last Friday.

The requirements for the sixth debate on Dec. 19 are even tougher. Candidates must have at least 200,000 unique donors and a minimum of 800 unique donors per state in at least 20 states. Candidates must also mark 4% in at least four national or early-state polls, or achieve 6% in two single-state polls in the early states. Polls must be released by approved pollsters between Oct. 16 and Dec. 12.

As of now, Biden, Buttigieg, Harris, Klobuchar, Sanders and Warren are the only six who have qualified for December.

The Associated Press contributed to this report.