The Note: Harris recasts race as Biden plays defense

The TAKE with Rick Klein

It wasn't just about a breakout moment or the fact that she took on the front-runner so directly.

What makes Sen. Kamala Harris' debate performance a potential game changer is at once more simple and more complicated than that.

By drawing on her biography and her background, Harris sought to speak for herself as well as expose vulnerabilities in former Vice President Joe Biden's record. It was about her, but also channeled a broader frustration about the candidates who are so far dominating polls of Democratic primary voters.

Biden, at times, has found himself defending his own record and even that of former President Barack Obama. That shows how much the party has changed, not just in his nearly five decades in public life, but inside just the two-plus years since the Obama-Biden era ended.

Biden's Democratic Party is not what it used to be. Neither, after the first debates of the 2020 cycle, is the race for president.

The RUNDOWN with MaryAlice Parks

Twice Thursday night, Biden was asked to defend Obama's legacy, and twice he looked rather uncomfortable.

First, he said he would let undocumented immigrants buy health care on Obamacare marketplaces, though the Affordable Care Act originally didn't allow that. Second, when Biden tentatively raised his hand about decriminalizing border crossings and then struggled to follow up when asked about Obama's record on deportations.

Perhaps it's a sign of how far left the party has lurched that other Democratic candidates are willing to distinguish themselves from the former president on several topics. Or maybe the lines of questioning simply exposed a potential weakness for the former vice president -- as in, whether he has ideas different from Obama's.

Going forward , is Biden going to have to get comfortable with the idea of criticizing Obama? Saying bluntly that he would do things differently now?

The TIP with John Verhovek and Lissette Rodriguez

The main event ended Thursday night, but the spotlight on one of the biggest topics of both nights -- immigration -- continues.

On Friday, six more Democratic presidential candidates will join South Florida Rep. Debbie Mucarsel-Powell at the Homestead Migrant Detention Center, ground zero for the contentious battle over family separations and the ongoing situation at the U.S.-Mexico border.

The site has seen the likes of Sen. Bernie Sanders, Sen. Elizabeth Warren and former Rep. Beto O'Rourke, but the latest horde of candidates includes former Housing and Urban Development Secretary Julián Castro. He led the charge on the conversation Wednesday night after insisting that his opponents say they agree with his policy proposal to decriminalize border crossings. Sen. Kamala Harris and South Bend, Indiana, Mayor Pete Buttigieg are also slated to join the visit.

Something to watch on Friday is how aggressive a pitch the candidates will make to gain access to the walled-off facility. Thus far, candidates have settled for step ladders and loud shouts to get their message across to the young men housed inside the facility, whose fates are still uncertain.

THE PLAYLIST

ABC News' "Start Here" podcast. "Start Here" is in Miami again to recap the second night of Democratic presidential debates. ABC News Deputy Political Director MaryAlice Parks walks us through the biggest moments of the night and we head into the spin room to get reaction from the candidates. Then ABC News Supreme Court Contributor Kate Shaw decodes Thursday's rulings about the citizenship question on the upcoming census and partisan gerrymandering. http://apple.co/2HPocUL

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The Note is a daily ABC News feature that highlights the key political moments of the day ahead. Please check back Monday for the latest.