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The 10 strongest Democratic presidential candidates, as measured by fundraising and polling, will face off in Houston from 8 to 11 p.m. ET on Thursday for the third Democratic debate. The three frontrunners in the middle of the stage at Texas Southern University will be former Vice President Joe Biden, Sen. Elizabeth Warren (D-Mass.), and Sen. Bernie Sanders (I-Vt.). This will be the first debate where all the eligible candidates will be on the same stage on the same night, and also the first time the steadily rising Warren and longtime frontrunner Biden will face off. That likely confrontation will be closely watched, but it isn't the only potential drama at the debate.

Perhaps the biggest question is the actual strength or fragility of Biden's frontrunner status. Warren and Sanders, the third member of the top tier, have similar policy ideas and have avoided antagonizing each other so far, but if Biden continues to dominate the center-left lane in the race, one of them has to rise to dominate the more liberal path.

Meanwhile, the other seven candidates — Sen. Kamala Harris (Calif.), South Bend Mayor Pete Buttigieg, Andrew Yang, Sen. Cory Booker (N.J.), Beto O'Rourke, Sen. Amy Klobuchar (Minn.), and Julián Castro — will be angling for a breakout moment. It can't involve swearing, either, the DNC and ABC News warned, because there will be no seven-second delay to catch any profanities. Yang has hinted he has something special planned.

The moderators of the debate, sponsored by ABC News and Univision, will be George Stephanopoulos, David Muir, Linsey Davis, and Jorge Ramos. It will air on ABC and Univision plus a full battery of online streaming services, including YouTube, Hulu, Facebook Watch, AppleTV, Twitter, and ABCNews.com and FiveThirtyEight.