The Note: Warren readies for spotlight at 1st 2020 debate

Sen. Warren will be center stage as the highest-polling candidate on Wednesday.

The TAKE with Rick Klein

They all need to have a plan for that -- and anything else that may come their way.

It starts with a candidate in the middle, who has seen her ideas and -- yes -- her plans, bubble into the conversation along with her poll numbers.

Sen. Elizabeth Warren gets either the very lucky or very unlucky position of being the highest-polling candidate on the stage Wednesday night. She'll be center stage, alongside former Rep. Beto O'Rourke, with Sens. Cory Booker and Amy Klobuchar and former Housing and Urban Development Secretary Julian Castro among those also looking for breakout moments.

Warren will seek to drive debate storylines even before then. Her relatively early calls for impeachment proceedings against President Donald Trump take on a new light with the news that former special counsel Robert Mueller will testify on Capitol Hill next month.

In a field where the haves get noticed for what they're doing and saying, and the have-nots get noticed primarily for who they're not, the initial debates mean different things for different candidates.

Warren gets a chance to build upon a welcome campaign moment. Still, this week marks the start of a long process -- the first debate among a dozen that were promised for candidates by the Democratic National Committee.

It's worth remembering that most of what smart political observers thought at this phase of the last cycle turned out to be very wrong -- all planning aside.

The RUNDOWN with MaryAlice Parks

The humanitarian crisis in government detention centers along the southern border will force 2020 Democratic presidential candidates to talk about immigration, whether they're ready or not.

Most Democratic candidates have not placed the issue at their center of their stump speeches or policy rollouts.

When they talk about the border, most candidates largely attack Trump's hard-line positions. They rail about the idea of building a wall and the administration's past policy of separating families.

Castro, the only Latino in the group, has been an exception. His proposal to decriminalize border crossings got Warren's endorsement on Tuesday. She's also making a late-morning visit to the shelter in Homestead, Florida, that's being used to house migrant children separated from their families.

"I'm going to Homestead tomorrow. Come with me," Warren told supporters in South Florida on Tuesday night, knowing full well that she likely will be turned away.

With so many sitting members of Congress running in the pack, primarily pointing fingers across the aisle will likely soon fall flat. They may not like this president's approach, but children are reportedly without blankets and toothpaste right now and those on Capitol Hill are in positions of power.

Voters are going to want to see both concrete plans for what they would do if elected president in 2020 as well as proof they can govern today.

The TIP with Sasha Pezenik

On opposite sides of the TV screen and from opposite coasts, Washington Gov. Jay Inslee and Rep. Tim Ryan, D-Ohio, will take the debate stage on Wednesday night. But like so many other candidates in Miami this week, they go way back -- to even closer quarters than the debate stage -- as onetime roommates in the nation's capital.

And Thursday night, Colorado's sons, former Gov. John Hickenlooper and Sen. Michael Bennet, will share the stage after having shared more than 15 years of friendship and public service working together. The Wesleyan University alumni worked together when Hickenlooper ran and then served as Denver mayor. Bennet eventually became the city's superintendent of public schools under Hickenlooper.

In South Carolina this past weekend, Hickenlooper and Bennet were asked how they feel going up against each other.

"Aww, I'm gonna come after him left and right!" Hickenlooper told ABC News. "Nah, he's probably the best senator we have. ... I feel lucky I know him."

"Well, he was an incredibly bad boss, so I might take it out on him," Bennet joked. "No that's not true at all, he was a great boss, great governor, I doubt very much I'm going to be taking anything out on John Hickenlooper. But, you never know!"

THE PLAYLIST

ABC News' "Start Here" podcast. Wednesday morning's episode features ABC News Chief National Correspondent Matt Gutman, who tells us why the acting head of Customs and Border Protections stepped down yesterday. Then ABC News Chief Political Analyst Matt Dowd gets us ready for Wednesday night's Democratic presidential debate, saying we can think about it like World Cup soccer and that this is the group stage that will show us who will make it to the knockout stage. http://apple.co/2HPocUL

ABC News' "Powerhouse Politics" podcast. Former Housing and Urban Development Secretary Julian Castro talks with ABC News Political Director Rick Klein and Senior Congressional Correspondent Mary Bruce ahead of his appearance in Miami at the first 2020 Democratic presidential debate on Wednesday. https://apple.co/2v6tkuR

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