Down Arrow Button Icon

With a midnight deadline fast approaching, frontrunner Joe Biden, Elizabeth Warren, Bernie Sanders, and Kamala Harris are locks Wednesday to participate in the third Democratic presidential debate next month in Houston, along with six others who met polling and fundraising thresholds required by the Democratic National Committee (DNC).

However, while Hawaii Congresswoman Tulsi Gabbard, New York Senator Kirsten Gillibrand, California climate change activist and billionaire Tom Steyer, and motivational speaker and author Marianne Williamson may have reached the fundraising threshold, it’s unlikely they will meet the polling minimum to debate.

Gillibrand saw the writing on the writing on the wall, tweeting Wednesday evening that she was dropping out of the race.

“Today, I am ending my campaign for president. I am so proud of this team and all we’ve accomplished,” she wrote. “But I think it’s important to know how you can best serve. To our supporters: Thank you, from the bottom of my heart. Now, let’s go beat Donald Trump and win back the Senate.”

Gillibrand and other candidates’ chances appeared even slimmer after two DNC-approved polls from Quinnipiac University and USA Today/Suffolk University released Wednesday didn’t change their standing. Biden has a commanding double-digit lead in both polls, despite being in a virtual three-way tie with Sanders and Warren in a third poll by Monmouth University released on Monday.

These latest poll findings effectively cut the Democratic debate field in half, as it’s now more likely the qualifying candidates will all appear on one stage, on one night at Texas Southern University on September 12.

Here’s the list of September debate candidates in alphabetical order:

Former Vice President Joe Biden
New Jersey Senator Cory Booker
South Bend, Indiana Mayor Pete Buttigieg
Former Housing and Urban Development Secretary Julián Castro
California Senator Kamala Harris
Minnesota Senator Amy Klobuchar
Former Texas Congressman Beto O’Rourke
Vermont Senator Bernie Sanders
Massachusetts Senator Elizabeth Warren
Businessman/tech entrepreneur Andrew Yang

Meanwhile, Steyer has received 2% in three of his four necessary qualifying polls, and Gabbard has reached 2% in only two qualifying polls. That’s a bit of a surprise considering Gabbard made news for questioning Harris’ record as the California attorney general during the second Democratic debate a month ago. Williamson has received 2% in one qualifying poll.

The remaining candidates, including Gillibrand and New York Mayor Bill de Blasio and Montana Gov. Steve Bullock, have not reached above 2% in any polls.

According to the DNC, all polls must be conducted by an approved pollster between June 28 and August 28. The polls also must be conducted nationwide, or in states with upcoming primaries or caucuses. Those states include Iowa, New Hampshire, South Carolina, and maybe Nevada.

The polls also must have a certain question structure, as well. Additionally, each candidate must receive at least 2% support in four or more of these polls, and they can’t be conducted by the same pollster in the same region.

These Are the Candidates Who Made the Next Democratic Debate

More must-read stories from Fortune: