The Note: Trump faces new narrative with primary challenge Bill Weld's entry into the 2020 GOP primary changes the narrative of the race.

The TAKE with MaryAlice Parks

It's official. Two paradigms have shifted. Sen. Bernie Sanders is a millionaire, and the millionaire in the White House will have a primary challenger.

Sanders, who has for decades delivered tough talk aimed at the wealthiest Americans, is now among those top earners, according to his tax returns that he released Monday evening.

And although he may not be a household name, former Massachusetts Gov. Bill Weld's formal entry into the 2020 Republican presidential primary changes the narrative of the entire race. The incumbent president who's struggled in the polls since taking office will not run unopposed.

Of course, the entire Republican Party apparatus is firmly behind President Donald Trump, and he enjoys an enormous financial leg-up over everyone, on both sides, as well as remarkable fundraising and grassroots prowess. It's hard to imagine Weld's campaign as more than an interesting asterisk at this point.

Still, if over the next eight months Weld gains steam or cracks the president's base in an early state, it could create ripple effects. According to Weld, a win would be enticing and could inspire others in the party, as well as independents, to rebel against the status quo.

In that way -- in a small way -- this early, longest-of-long-shot bids has an air similar to Sanders from the last cycle.

The RUNDOWN with John Verhovek

As he continues to teeter on the edge of announcing a presidential campaign, former Vice President Joe Biden is slated to deliver a eulogy for legendary South Carolina Sen. Ernest "Fritz" Hollings on Tuesday. Hollings was Biden's desk-mate and one of his closest confidants in the chamber during his 36-year Senate career.

The speech is another chance for Biden to move past the scramble that ensued after his past behavior around women and his reaction to the concerns they raised came under scrutiny. It's also an opportunity to hearken back to his status as one of the country's most-established statesmen.

While Biden's eulogy is sure to regale the many years he and Hollings shared as colleagues, his presence in the early-primary state of South Carolina so close to his anticipated presidential announcement is hard to ignore.

Also eulogizing Hollings will be House Majority Whip Jim Clyburn, the most senior African American lawmaker in the U.S. House and a key player in South Carolina politics who's been in regular contact with Biden about a potential bid.

The Palmetto State will be key to a Biden candidacy, as will the South in general, where African American voters carry huge sway and more than 15 candidates may be asking for their votes.

The TIP with Christopher Donato

Small-city mayor-turned-presidential contender Pete Buttigieg might be looking to add one more title to his growing list of monikers: father. The 37-year-old opened up about his hopes for the future when asked about paid family leave at a grassroots fundraiser in Brooklyn, New York, on Monday.

"We're hoping to have a little one soon, so have a personal stake in this one," he said. "We should have paid parental leave and find a way to have paid leave for anyone who needs caring."

He also pointed to a paid-family-leave policy he implemented in South Bend, Indiana, saying it shaped "a better employer and city." Later, on MSNBC, he admitted that his ambitions and unexpected rise might delay his family plans with his husband, Chasten.

"This running for president has slowed down the path," he conceded.

THE PLAYLIST

ABC News' "Start Here" podcast. Tuesday morning's episode features ABC News' David Wright in Paris, where he tells us more about the devastating fire that engulfed the historic Notre Dame cathedral. Then Krupali Uplekar, a professor at Notre Dame University, explains the long restoration process that lies ahead. ABC News Senior Editorial Producer John Santucci tells us what to expect when Attorney General William Barr releases a redacted version of the Mueller report on Thursday. And ABC News Deputy Political Director MaryAlice Parks breaks down what we learned from Sen. Bernie Sanders' batch of personal tax returns. http://apple.co/2HPocUL

ABC News' "The Investigation" podcast. The Mueller report, with color-coded redactions, is expected to be made public this week, 675 days, 2,800 subpoenas and 500 witness interviews later. Now, the ABC News Investigative team is taking you inside the "War Room" where the team will read through and report back all the details once the report is released. In this episode of "The Investigation," co-host Chris Vlasto and ABC News' John Santucci and Matt Mosk break down everything you need to know about the upcoming release of the Mueller Report with Chief White House Correspondent Jon Karl and Legal Analyst Dan Abrams. https://apple.co/2uV2eH1

FiveThirtyEight's "Politics Podcast." First-quarter financial reports for presidential campaigns were due to the Federal Elections Commission on Monday. So the FiveThirtyEight Politics podcast crew takes the opportunity to assess the state of the Democratic primary with the first quarter of the year in the rearview mirror. https://53eig.ht/2v5wIpJ

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