Rep. Al Green, Democrat of Texas, was a maverick when he started trying to impeach President Trump in 2017. Tuesday, his party took that remarkable step formally, when House Speaker Nancy Pelosi announced an impeachment inquiry into the president. Over 95 percent of House Democrats, plus one independent, now are openly supportive of that investigation, following rapidly developing news that Trump had talked to the president of Ukraine about investigating a political opponent — and withheld nearly $400 million in aid from the country.

In between, Democratic support for an impeachment inquiry has grown in fits and starts, often corresponding to key junctures in the many investigations of the 45th president, including that of Special Counsel Robert S. Mueller III.

Sept. 27 | 225 Following Ukraine relevations and Pelosi announcing an impeachment inquiry 200 Democrats 150 July 24 | 95 Mueller testifies to House Judiciary Committee days before August recess 100 May 20 | 27 Trump bars former White House counsel Don McGahn from testifying before the House Judiciary Committee 50 0 July January 2019 July 2017 January 2018 July Sept. 27 | 225 Following Ukraine relevations and Pelosi announcing an impeachment inquiry 200 Democrats 150 July 24 | 95 Mueller testifies to House Judiciary Committee days before August recess 100 May 20 | 27 Trump bars former White House counsel Don McGahn from testifying before the House Judiciary Committee 50 0 July 2017 January 2018 July January 2019 July Sept. 27 | 225 Following Ukraine relevations and Pelosi announcing an impeachment inquiry 200 Democrats July 24 | 95 Mueller testifies to House Judiciary Committee days before August recess 150 100 May 20 | 27 Trump bars former White House counsel Don McGahn from testifying before the House Judiciary Committee 50 0 July 2017 January 2018 July January 2019 July Sept. 27 | 225 Following Ukraine relevations and Pelosi announcing an impeachment inquiry 200 Democrats 150 July 24 | 95 Mueller testifies to House Judiciary Committee days before August recess 100 May 20 | 27 Trump bars former White House counsel Don McGahn from testifying before the House Judiciary Committee 50 0 July 2017 January 2018 July January 2019 July

Even with her caucus support seemingly sure and one independent supporting impeachment, Pelosi needs more votes in the full House to pass actual articles of impeachment, which would then be sent to the Republican-controlled Senate.

Before the redacted Mueller report was released

Prior to mid-April 2019

2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 TRUMP +25 EVEN +75 +25 Other House Democrats Support impeachment inquiry 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 TRUMP +25 EVEN +75 +25 Rep. Yarmuth (KY-3) Rep. Tlaib (MI-13) Other House Democrats Support impeachment inquiry 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +75 CLINTON +50 CLINTON +25 EVEN TRUMP +25 Rep. John Yarmuth (KY-3) Rep. Rashida Tlaib (MI-13) Other House Democrats Support impeachment inquiry 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +75 CLINTON +50 CLINTON +25 EVEN TRUMP +25 Rep. John Yarmuth (KY-3) Rep. Rashida Tlaib (MI-13) All other House Democrats Support impeachment inquiry 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +75 CLINTON +50 CLINTON +25 EVEN TRUMP +25 Rep. John Yarmuth (KY-3) Rep. Rashida Tlaib (MI-13) All other House Democrats Support impeachment inquiry

By March of this year, newly elected congresswomen Rashida Tlaib (Mich.), who hours before her swearing in said “we’re gonna impeach the motherf-----," introduced a resolution with Green. About a dozen House Democrats had announced support for an impeachment inquiry by April. Hillary Clinton won every district these early supporters represent — all but one by more than 40 points.

Then came the long-awaited release of the Report on the Investigation into Russian Interference in the 2016 Presidential Election, commonly known as the Mueller report, on April 18.

Following the Mueller report release

Mid-April to the end of May

2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 EVEN TRUMP +25 +75 +25 Other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 TRUMP +25 EVEN +75 +25 Rep. Malinowski (NJ-7) Rep. Waters (CA-43) Other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT TRUMP +25 CLINTON +75 CLINTON +50 CLINTON +25 EVEN Rep. Tom Malinowski (NJ-7) Rep. Maxine Waters (CA-43) Other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT EVEN TRUMP +25 CLINTON +75 CLINTON +50 CLINTON +25 New supporters Rep. Tom Malinowski (NJ-7) Rep. Maxine Waters (CA-43) All other House Democrats Other supporters 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +75 CLINTON +50 CLINTON +25 EVEN TRUMP +25 Rep. Tom Malinowski (NJ-7) Rep. Maxine Waters (CA-43) All other House Democrats Other supporters New supporters

That brought the first spike of support for an impeachment inquiry. The report detailed 10 instances of possible obstruction of justice by Trump, setting off a firestorm in the Democratic caucus. Soon after its release, many more members from safe Democratic districts announced their support. Among those were the other members of the squad who signed onto Tlaib’s resolution.

During this time period, the administration also blocked former White House Counsel Don McGahn from testifying in relation to the report, saying he was “absolutely immune” from compelled congressional testimony. Several lawmakers came out for impeachment in the following days.

Pelosi allies and moderates mostly preferred additional investigations over impeachment proceedings at this point, as the speaker said “if the . . . fact-finding takes us there, we have no choice. But we’re not there yet.”

“Mueller kicked the impeachment ball to the Congress. The Constitution gives the responsibility to Congress to impeach an unfit president — ‘high crimes and misdemeanors.’ What more do we need?” Rep. Maxine Waters (Calif.), chair of the House Financial Services Committee, tweeted.

[Which House Democrats want to open an impeachment inquiry into Trump]

Following the Mueller public statement

End of May to mid-July

Dozens more across the caucus came out in support of an inquiry in late May, after Mueller spoke publicly about his investigation’s findings. In the statement, Mueller cited Justice Department policy for his inability to charge Trump, tossing the matter to Congress and upping the pressure on Pelosi.

“Many constituents want to impeach the president. But we want to do what is right and what gets results,” Pelosi said at the time.

“The special counsel did not give any indication that the president is innocent,” Rep. Bennie Thompson (Miss.) said, in pushing for impeachment proceedings.

Following the Mueller testimony

Mid-July to mid-September

2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 EVEN TRUMP +25 +75 +25 Other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 TRUMP +25 EVEN +75 +25 New supporters Rep. Pappas (NH-1) Other House Democrats Other supporters Rep. Underwood (IL-14) 2016 PRESIDENTIAL RESULT IN DISTRICT TRUMP +25 CLINTON +75 CLINTON +50 CLINTON +25 EVEN Other supporters Rep. Lauren Underwood (IL-14) Other House Democrats Rep. Chris Pappas (NH-1) New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT TRUMP +25 CLINTON +75 CLINTON +50 CLINTON +25 EVEN Rep. Lauren Underwood (IL-14) Other supporters All other House Democrats New supporters Rep. Chris Pappas (NH-1) 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +75 CLINTON +50 CLINTON +25 EVEN TRUMP +25 Rep. Chris Pappas (NH-1) Other supporters All other House Democrats Rep. Lauren Underwood (IL-14) New supporters

More than 40 additional Democrats supported impeachment after Mueller’s testimony to the House Judiciary Committee on July 24 and during the August recess, including the first lawmakers from districts that Trump won. Reps. Chris Pappas (N.H.) and Lauren Underwood (Ill.) were the first to do so.

One of them was Rep. John Garamendi (Calif.), who, in an interview with The Post on July 25, compared an inquiry to grand jury proceedings. First, open an impeachment inquiry, he said, then “we will see where we go with an impeachment, a formal resolution.”

That same day, Trump spoke with Ukrainian President Volodymyr Zelensky. His conversation would emerge in a whistleblower complaint filed in August. The Post has reported that Trump urged Ukraine to investigate former vice president and 2020 presidential candidate Joe Biden and his son Hunter as the administration was holding up congressional appropriations of military and intelligence aid.

Hunter Biden served for nearly five years on the board of Burisma, Ukraine’s largest private gas company, whose owner came under scrutiny by Ukrainian prosecutors for possible abuse of power and unlawful enrichment. Hunter Biden was not accused of any wrongdoing in the investigation. As vice president, Joe Biden pressured Ukraine to fire the top prosecutor, Viktor Shokin, who Biden and other Western officials said was not sufficiently pursuing corruption cases. At the time, the investigation into Burisma was dormant, according to former Ukrainian and U.S. officials.

By that time, the House Judiciary Committee had started an investigation into whether it would recommend articles of impeachment against Trump.

Rep. Jerrold Nadler (D-N.Y.), chairman of the Judiciary Committee and a Pelosi ally, confirmed the probe in an Aug. 8 interview with CNN and is likely to oversee the impeachment inquiry announced Tuesday.

As the whistleblower story broke

Mid-September, as of Sept. 27, 5 p.m.

2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 EVEN TRUMP +25 +75 +25 Other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +50 EVEN TRUMP +25 +75 +25 Speaker of the House Nancy Pelosi Rep. Angie Craig (MN-2) Other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT TRUMP +25 CLINTON +75 CLINTON +50 CLINTON +25 EVEN Speaker of the House Nancy Pelosi Rep. Angie Craig (MN-2) Other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT TRUMP +25 CLINTON +75 CLINTON +50 CLINTON +25 EVEN Speaker of the House Nancy Pelosi Rep. Angie Craig (MN-2) All other House Democrats Other supporters New supporters 2016 PRESIDENTIAL RESULT IN DISTRICT CLINTON +75 CLINTON +50 CLINTON + 25 EVEN TRUMP +25 Rep. Angie Craig (MN-2) Speaker of the House Nancy Pelosi All other House Democrats Other supporters New supporters

As Trump this week first acknowledged that he spoke with Zelensky about Biden, then admitted he withheld the aid, while giving various explanations for that decision, a barrage of moderates moved toward impeachment. Several have backgrounds in national security.

“The president of the United States may have used his position to pressure a foreign country into investigating a political opponent, and he sought to use U.S. taxpayer dollars as leverage to do it,” seven freshman Democrats from competitive districts wrote in a Post op-ed backing an inquiry. They were among the dozens of lawmakers who moved to “yes” in a 24-hour span.

“There comes a time when you have to be moved by the spirit of history to take action to protect and preserve the integrity of our nation. I believe, I truly believe, the time to begin impeachment proceedings against this president has come,” Rep. John Lewis (Ga.), a close Pelosi ally who had long remained quiet on the matter, said on the House floor. “To delay or to do otherwise would betray the foundation of our democracy.”

On Tuesday, amid mounting pressure from all sides of her caucus, Pelosi took the step she had long avoided.

About this story

The Fix impeachment tally compiled by JM Rieger. 2016 election results from Dave Leip’s U.S. Election Atlas. Pennsylvania’s congressional districts were redrawn in 2018. The Trump-Clinton margin shown was calculated for the new geographic area.

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