The TAKE with Rick Klein

Impeachment has now moved to a phase where there's probably nothing the White House can do to stop it. That's some unfamiliar territory for President Donald Trump.

The launch of an official "impeachment inquiry" means congressional Democrats are now acting, with Trump left reacting. Wednesday's promised release of the transcript between Trump and the Ukrainian president won't be enough to quiet things down, not with even the Senate now on record demanding the full whistleblower complaint.

House Speaker Nancy Pelosi's announcement leaves plenty of questions of what happens from here, including whether a vote is ever held on the House floor. But that will be for Democrats to decide, now that constitutional levers are being pulled.

The move injects additional uncertainties into the climate in Washington and the 2020 race.

But one very big question has been answered, in a way that has Democrats instigating actions instead of maneuvering around the president.

The RUNDOWN with MaryAlice Parks

The allegations stemming from a call with a Ukrainian leader might be new, but they landed at a time when stonewalling and non-compliance from the Trump administration was getting really old for Democrats on Capitol Hill.

Just last week, the White House blocked two former staffers from testifying before the House Judiciary Committee. The White House claimed executive privilege and Chairman Jerry Nadler, D-N.Y., called the move "an absolute cover up."

The one witness present, the president's former campaign manager Corey Lewandowski, repeatedly refused to answer questions too, which led Nadler to declare, "The Trump administration will do anything and everything in its power to obstruct Congress' work."

Last month, the House Judiciary Committee filed a motion to try and expedite a lawsuit about whether former White House Counsel Don McGahn could be compelled to testify too about events in the Mueller report. All the stalling and delays left these House chairmen frustrated and insulted, and the acting director of national intelligence refused to comply with a subpoena demanding that whistleblower complaint -- regarding the president's call with a foreign leader -- be sent along to Congress.

As Speaker Nancy Pelosi emphasized on Tuesday, the Constitution is "enshrined in three co-equal branches of government," but Democrats have felt hamstrung for a long time. One big question now: Will the impeachment inquiry help Democrats get answers and testimony on these other questions, or will it be limited to a back-and-forth on Ukraine?

THE TIP with Will Steakin

While Republicans on Capitol Hill remain steadfast behind President Trump as his presidency propels toward an impeachment inquiry, two long-shot GOP primary challengers vigorously rebuked the president’s actions at an unsanctioned primary debate Tuesday night, in what at times felt like a Republican alternate universe.

“Let me start like this. The president of the United States will be impeached very, very soon. [Trump] will deserve to be impeached very, very soon,” former Congressman Joe Walsh railed in his opening remarks at Tuesday's debate with fellow long-shot candidate Bill Weld, hosted by Business Insider.

And while the theme of the night was Trump’s unfitness for office, the underlying message saw both Weld and Walsh look to the future and attempt to offer a counter GOP vision, despite the president’s high approval rating among Republicans.

“You will have seen tonight, from both me and the congressman, that there are tired-and-true Republicans,” Weld said in his closing remarks. But the big question, with active viewers peaking at under 1,000 for the debate, is what's the appetite for an alternative to Trump's Republican party?

THE PLAYLIST

ABC News' "Start Here" podcast. Wednesday morning's episode features ABC News Senior Congressional Correspondent Mary Bruce and ABC News White House Correspondent Karen Travers on the implications of the impeachment inquiry. Then, ABC News Foreign Correspondent James Longman breaks down the U.K. Supreme Court's rebuke of Prime Minister Boris Johnson. http://apple.co/2HPocUL

WHAT YOU NEED TO KNOW TODAY

Former astronaut Mark Kelly, who is running in the Democratic primary for the late John McCain's Senate seat in Arizona, appears on ABC's "The View" at 11 a.m.

Former Vice President Joe Biden joins ABC's "Jimmy Kimmel Live" at 11:35 p.m.

President Donald Trump has a multilateral meeting on Venezuela at 10 a.m., a bilateral meeting with the prime minister of Japan at 12:10 p.m., a bilateral meeting with the president of Ukraine at 2:15 p.m., a bilateral meeting with the president of El Salvador at 3:15 p.m., a press conference at 4 p.m. and speaks at a joint fundraising committee dinner at 7:40 p.m.

Vice President Mike Pence meets with Veterans Affairs Secretary Robert Wilkie in the White House at 3:45 p.m.

Biden attends Biden for President fundraising events in Manhattan Beach and Bel Air, California.

Sen. Bernie Sanders, I-Vt., joins the UAW Picket Line at General Motors' Detroit-Hamtramck Assembly in Detroit starting at 10:30 a.m. (CDT).

Former Rep. Beto O'Rourke, D-Texas, participates in a Service Employees International Union roundtable at the University of Pittsburgh. Afterwards, he holds a town hall in Schenley Plaza in Pittsburgh. Later, he participates in a community roundtable in Warren, Ohio. Then, he joins the Lordstown UAW Strike at the GM Corporation in Warren. To end the day, he holds a town hall at Kent State University.

Former Housing and Urban Development Secretary Julián Castro visits Fruitvale Station in Oakland, California, where a black man was killed by a Bay Area Rapid Transit (BART) police officer in 2009, at 11:15 a.m. (PST). Later, he tours a homeless encampment site in Oakland at noon. After, he attends a Latino Heritage Celebration with Mayor London Breed in San Francisco at 5 p.m.

Sen. Kamala Harris, D-Calif., holds a tele-town hall with Nevadans at 3 p.m. (PST).

Sen. Elizabeth Warren, D-Mass., holds a town hall at Keene State College in Keene, New Hampshire, at 5:30 p.m.

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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.