WASHINGTON (AP) — Same stage. Same rules. But the Democrats' second back-to-back debate is fueled by star power.

Debate night No. 2 marks the first time top-tier presidential candidates will confront one another in person over who is the best fit to lead the Democratic effort to oust President Donald Trump in 2020.

The sheer star power of the showdown Thursday at 9 p.m. Eastern amps up the pressure on candidates to stand out, pile on, fend off attacks or just survive. It's Joe Biden's night to show he commands the field. But it's Bernie Sanders' chance to show he's the one who understands today's Democratic Party. Pete Buttigieg could try to sound like a leader on the national stage, and Kamala Harris may aim to make a more personal impression.

For all 10 candidates on stage in Miami, the forum is a chance for Americans to try to picture the contenders as formidable foes to Trump over two hours of lightning-round questions.

Here's what to watch on the second night of the first presidential debates, airing on NBC, MSNBC and Telemundo:

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BIDEN VS. SANDERS

Ten candidates will be on stage. But two — Biden and Sanders — will most starkly represent the divide over the direction of the Democratic Party.

Sanders, a Vermont senator and self-proclaimed democratic socialist, has proudly pushed the party to the left, arguing that Democrats must embrace the progressive base that fueled his insurgent 2016 presidential bid. Many of his 2020 rivals have paid attention, embracing proposals such as "Medicare for All" that have been on the fringe in prior elections.

Biden, however, has resisted the leftward lurch. He rarely invokes Sanders by name but bemoans the idea that to be seen as a liberal today, candidates must embrace socialism . He argues that such moves will turn off the very working-class voters who moved away from Democrats in 2016 to embrace Trump.

Expect plenty of skirmishes between these two. Sanders has already knocked Biden for his vote backing the Iraq War and derided his big-money fundraisers. The former vice president has tried to stay above the fray — but that task could get harder under the glare of the debate stage spotlight.

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HARRIS AND GILLIBRAND

The other candidates on stage aren't likely to let Biden and Sanders suck up all the oxygen. For White House hopefuls like Harris, a senator from California, and Kirsten Gillibrand, a senator from New York, the debate offers a crucial opportunity to break through the crowded field.

Harris has successfully used her perch on Capitol Hill to create viral moments that highlight her prosecutorial past , including her tough questioning of Attorney General William Barr. But she's struggled to convey — in quick sound bites — who she is as a human being. She's tried to get more personal recently , talking about watching her mother struggle with racism. Watch to see whether she goes further tonight.

For Gillibrand, the debate could be a make-or-break moment as she's struggled to make inroads in polls and fundraising. She's an unabashed feminist on the campaign trail and will likely try to rally women with a passionate defense of reproductive rights.

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MAYOR PETE'S MOMENT

Buttigieg has been the darling of the Democratic Party for months. The mayor of South Bend, Indiana, who is gay and an Ivy League-schooled military veteran, is seen as a potentially effective opponent against Trump.

But he walks onto the debate stage confronting some of the toughest issues in American life: race and policing.

He has been criticized back home for his handling of a fatal police shooting of a black man. He'll likely be confronted about his record as mayor and his management of a largely white police department.

He seemed to test some potential debate night messages during a fundraiser this week.

"Leadership consists of facing reality," he said. "And right now, I'm afraid our leaders at the national level are at war with reality."

But just by being there, the 37-year-old Buttigieg makes age and the future of the party an issue. Watch to see if he can cast his challenges as experience that qualifies him to lead the nation.

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HEALTH CARE, IMMIGRATION

The future of health care split Democrats during the first debate , with only Massachusetts Sen. Elizabeth Warren and New York City Mayor Bill de Blasio saying they'd back the abolition of private insurance. Watch for more divides on Thursday. Sanders' Medicare for All proposal doesn't include private insurance, but Biden hasn't been willing to embrace such an approach.

Meanwhile, the searing photo of a father and daughter face-down in the Rio Grande has dominated talk of the migrant crisis this week. Look to see if Democrats offer many detailed proposals of their own beyond criticizing Trump's hard-line immigration policy .

Biden released part of his immigration plan on Monday, proposing that Congress grant immediate citizenship to 800,000-plus U.S. residents who were brought to the country illegally as children. But his outline was heavier on barbs at Trump.

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MCCONNELL, MCCONNELL, MCCONNELL

The Republican Senate majority leader said this week that he'd rather watch a baseball game than the Democratic debates. But the Democrats and moderators couldn't stop talking about him during Wednesday's face-off, giving him as much or more airtime than Trump. Key to the McConnell discussion was his drive to fill the courts and deny Democrats a chance to reshape the Supreme Court.

Listen to see if the Kentucky Republican makes another virtual star turn on Thursday night. Earlier Thursday, the high court dealt a huge blow to efforts to combat the drawing of electoral districts for partisan gain but also put a hold on the Trump administration's effort to add a citizenship question to the 2020 census .

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