The Note: Bernie v. Biden promises more aggressive debate night Joe Biden's name didn't come up Wednesday, but that will change Thursday.

The TAKE with Rick Klein

Somehow, former Vice President Joe Biden's name didn't come up on Wednesday night. That will change as soon as the candidates are introduced on Thursday.

The anticipated showdown between Biden and Sen. Bernie Sanders -- to say nothing of the other candidates -- reflects the long-running disagreements on policy and attitude inside the Democratic Party. That could liven things up after a mostly genial wonkfest that led things off for the party at the first debate.

But if the expected heat between the two polling front-runners is the main event, it's only part of the potential story.

There's also Mayor Pete Buttigieg, coming off of a week of being tested in the public eye. Sen. Kamala Harris will have chances to show off her prosecutorial skills on her own behalf. And two true outsiders -- Marianne Williamson and Andrew Yang -- get to show how they earned their spots in the first place.

For as strong as both Biden and Sanders appear in polls, neither has actually been part of a presidential debate in which he was a focal point or a major target.

Sanders' 2016 campaign was that of the perpetual underdog, leaving him more closely watched for what he would say about Hillary Clinton than the other way around. Biden's ill-fated 1988 and 2008 runs are remembered mostly for their premature conclusions, as opposed to debates.

The two older white men will be in the middle of the stage, but that doesn't necessarily put them in the middle of all the action.

The RUNDOWN with MaryAlice Parks

He might not have had the most air time, but former Rep. John Delaney landed a defining line on Wednesday night.

He said, "We need real solutions, not impossible promises," and with that, seemed to foreshadow the coming points of tension in this primary.

Night one of the Democratic presidential debates was largely full of agreements. The candidates tried to redefine their party more than define each other.

They made it clear that disagreeing with President Donald Trump's policies is not going to cut it for their Democratic base of voters. Instead, they pitched proposals that could swing the country in a dramatically different direction.

But focusing primarily on party values can only last so long. With a field focused on policy prescriptions, there's much for these candidates to explain on how exactly they will pay for or implement their wish lists.

The TIP with Sasha Pezenik

In sickness and in health, for better or for worse, to campaign and to support. Maybe that's not what they promised at the altar, but as their partners prepped for the debates, several 2020 spouses have stepped up as campaign surrogates.

Sen. Bernie Sanders' wife, Jane, beat him to the Homestead Detention Center, where many presidential hopefuls are visiting while in Florida. Jane told reporters that closing detention facilities would be her husband's first executive order if he takes the White House. Gov. Jay Inslee's wife, Trudi, helped him with prep. She's been largely quiet on the trail, but Wednesday morning she commandeered his Twitter account. "He's busy getting ready for the debate ... so I'm taking over," she said in a video, then leafed through their family album.

Former Rep. Beto O'Rourke's wife, Amy, tagged along for his pre-debate walk-through on Wednesday, Beto putting his hand on her shoulder as they stood at the podium. Chasten Buttigieg was also spotted with husband Mayor Pete Buttigieg ahead of his appearance Wednesday.

And while some couples took the stage, others were out and about. Rep. Tulsi Gabbard's husband, Abraham, kept up during an intense morning bootcamp. And while some burned calories for pre-debate destress, others enjoyed them, Sen. Kamala Harris' husband, Doug, shared a photo of them out on the town "enjoying some great Miami cuisine."

THE PLAYLIST

ABC News' "Start Here" podcast. "Start Here" heads to Miami for Thursday morning's episode to bring you highlights from the first night of Democratic presidential debates. And ABC News Senior Washington Reporter Devin Dwyer tees up what could be a historic day at the Supreme Court, with decisions expected on partisan gerrymandering and the 2020 census. http://apple.co/2HPocUL

ABC News' "Powerhouse Politics" podcast. Just hours ahead of the first Democratic presidential debate, former Housing and Urban Development Secretary Julián Castro joined ABC News Political Director Rick Klein and ABC News Chief Congressional Correspondent Mary Bruce to talk about his preparations and plans to visit the Homestead Child Detention Center outside of Miami on Friday. "I wouldn't call it a stunt," he said of his and other candidates visiting the facility. "I would say they were calling attention to the fact -- No. 1 -- that we need to end this kind of detention and make sure that people can get to, either family members who live in the United States or caregivers who are willing to take care of them, as soon as possible." https://bit.ly/2FA0CIm

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