The Note: Michael Bloomberg out of the running, but not the race Imagine the power of a Bloomberg endorsement down the road.

The TAKE with MaryAlice Parks

He may not be running for president, but Michael Bloomberg could have just as much influence on the future of the Democratic Party from outside the primary process.

Tuesday, the businessman and former New York City mayor announced he would not seek the Democratic Party's presidential nomination, but he committed to staying involved.

On issues like gun control and climate change, Bloomberg said he's not going to wait for politicians to act or for the next wave of elections. He plans to use his wealth, influence, organizations and advocacy to try to move the needle now. The results -- on future conversations and policy proposals -- could be big.

Imagine too, the power of a Bloomberg endorsement down the road.

"I come out of the business world. I've had executive jobs in both the private sector and government," he wrote in his column. "I think this is exactly what our country needs in a president."

Yes, plenty of progressives say he is too centrist for the party -- part of the reason he, no doubt, decided not to run -- but others value his opinion hugely. And Bloomberg will have the resources to help his pick get seen and heard.

The RUNDOWN with Rick Klein

A week that will be remembered for expanded investigations will also be recalled for the contracting field of undecided Democrats. Ahead of Bloomberg's announcement, Hillary Clinton, Sen. Jeff Merkley and former Attorney General Eric Holder each said they would sit out the 2020 race.

Fewer challengers, though, doesn't mean fewer challenges facing President Donald Trump. That, in part, explains the fierce reaction Trump and his associates have had to the requests for documents and information from a wide range of people and entities close to the president.

"Basically, they've started the campaign," Trump said Tuesday. "So the campaign begins."

It's an inevitably political response to procedural and legal questions with undeniable political overtones.

The breadth of the Democrats' investigation is being matched by a Trump-led Republican focus -- and discipline -- portraying it all as an attempt to end Trump's presidency by whatever means Democrats can muster.

The TIP with Adam Kelsey

Though much of Democrats' 2020-related attention continues to focus on the presidential who's-in/who's-out roller coaster, the party is quietly building a notable bench of Senate candidates as it seeks to avenge its 2018 losses and make another play for a majority in the chamber.

On Tuesday, Wendy Davis -- best known for her 11-hour state senate filibuster in 2013 over a bill restricting abortions -- told the Associated Press that she's considering challenging incumbent Sen. John Cornyn. Though Davis lost the governor's race by more than 20 points, she did so in a down year for Democrats and showed an ability to attract headlines and fundraise.

Elsewhere, Democrats have Mark Kelly, a nationally known astronaut, running in Arizona -- a state that already delivered a seat in 2018 -- and one of the party's biggest names in Stacey Abrams considering a challenge in Georgia of Sen. David Perdue.

None of the races could even approach being called a sure thing, but flipping just those three seats could result in a 50-50 draw in the chamber. Factor in more competitive elections in Iowa, where former Agriculture Secretary and Gov. Tom Vilsack or Rep. Cindy Axne could be recruited to run, plus Colorado, Kansas, Maine and North Carolina where the party performed strongly in 2018, and you've got intrigue far beyond the top of the ticket.

THE PLAYLIST

ABC News' "Start Here" Podcast. Wednesday morning's episode features ABC News White House Correspondent Tara Palmeri, who says a fight over access to Trump's tax returns could go all the way to the Supreme Court. http://apple.co/2HPocUL

WHAT YOU NEED TO KNOW TODAY

President Donald Trump greets Danny Burch, an American who was held hostage in Yemen, at 2 p.m. in the Oval Office. Later, he meets with Rep. Adam Kinzinger, R-Ill., and participates in an American Workforce Policy Advisory Board Meeting at 2:45 p.m. and 4 p.m., respectively.

Michael Cohen, the president's former personal attorney and fixer, appears privately before the House Intelligence Committee at 9:30 a.m. in Washington.

The House Homeland Security Committee holds a hearing on "The Way Forward on Border Security" with Secretary of Homeland Security Kirstjen Nielsen at 10 a.m. in Washington.

The Senate Judiciary Committee discusses the "Oversight of Customs and Border Protection's Response to the Smuggling of Persons at the Southern Border" at 10 a.m. in Washington.

The House Judiciary Committee conducts a hearing on "Protecting Dreamers and TPS Recipients" at 10 a.m. in Washington.

Former Georgia gubernatorial candidate Stacey Abrams speaks on "Democracy and the Politics of Identity" in London.

Howard Schultz, Former Starbucks CEO and author of "From The Ground Up: A Journey To Reimagine The Promise Of America" delivers a keynote speech at Rice University at 6:30 p.m. local time in Houston.

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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 tomorrow for the latest.