By the end of the day, the civil rights hero was joined by three of his colleagues from Georgia: U.S. Reps. Hank Johnson of Lithonia, David Scott of Atlanta and Sanford Bishop of Albany.

Johnson said Trump’s recent admission that he pressed Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his family is “profoundly troubling.”

“Attempting to coerce a foreign government into digging up dirt on a political opponent, then trying to cover it up by unlawfully refusing to turn over the whistleblower complaint to Congress, crosses a red line,” Johnson said in a statement to The Atlanta Journal-Constitution.

The sudden shift put Georgia Republicans on the defensive. U.S. Sen. David Perdue, a loyal Trump ally who is up for re-election next year, called on Democrats to “move on and start legislating instead of all this investigating.”

“They’ve weaponized politics here. They have obstructed this president since day one,” said the first-term Republican. “They just can’t get over that he won the election, and so I just see this as premature.”

In an even trickier spot was freshman Congresswoman Lucy McBath, D-Marietta, whose 2018 upset victory in a Republican-leaning suburban district was the state party’s crowning achievement in the midterm. She refused to answer reporters’ questions following a closed-door meeting with Pelosi and other Democrats on Tuesday afternoon.

‘The time to act’

Johnson and Lewis are outspoken critics of Trump who have opposed his policies, criticized his agenda and boycotted his key speeches. But the two had resisted calling for his impeachment, echoing Pelosi’s argument that more investigation was needed.

Their stance changed with the reports alleging that Trump and his personal lawyer prodded the Ukrainian leader to probe Biden, the Democratic presidential front-runner, as his administration refused to hand over a whistleblower complaint detailing the claims.

Trump has acknowledged he mentioned the Bidens in a call with Zelensky, but he denied that he withheld military aid from the country to pressure Ukraine to do his bidding.

“It’s a witch hunt,” Trump told reporters in New York. “I’m leading in the polls. They have no idea how to stop me. The only way they can try is through impeachment.”

The demand for impeachment reached a dramatic peak when Lewis, a moral leader among House Democrats, declared “now is the time to act” as he dropped his opposition.

“We will never find the truth unless we use the power given to the House of Representatives - and the House alone - to begin an official investigation as dictated by the Constitution,” he said. “The future of our democracy is at stake.”

Johnson, a senior member of the House Judiciary Committee that has jurisdiction over impeachment matters, became the first congressman in Georgia to support the move.

He was later joined by Bishop and Scott, two more centrist colleagues who had previously dodged the limelight on impeachment.

Read more: John Lewis backs impeachment: "To delay would betray the foundation of our democracy"

Democratic U.S. Reps. David Scott (L), John Lewis (C) and Hank Johnson (R) in 2012. Credit: Tamar Hallerman Credit: Tamar Hallerman

Scott framed his thinking in terms of national security and said “Congress must exercise its duties as a co-equal branch of government to preserve the checks and balances laid out in the Constitution.”

Bishop, a senior member of the House Appropriations Committee, said reporting that alleged Trump withheld aid money previously approved by Congress was “extremely alarming.”

“﻿Taken with the Mueller report and the facts discovered by the other ongoing Committee investigations, we have reached a point where Congress must move forward with an impeachment inquiry,” he said.

A breakneck pace

GOP lawmakers from Georgia largely watched Tuesday’s developments from the sidelines, but those who did wade into the debate slammed Democrats for racing prematurely toward impeachment. Trump promised to release an unredacted transcript of his conversation with Zelensky on Wednesday, which he said was "totally appropriate" and didn't include a "quid pro quo."

U.S. Rep. Buddy Carter, R-Pooler, said Democrats’ impeachment push “have less to do with anything (Trump) has done than Washington Democrats’ blind hatred of him.”

“Three years after his election, they still can’t get over the fact he won,” the three-term congressman tweeted. “If they cared what was said on the call, they would wait for the transcript rather than launching impeachment off second hand, leaked information.”

More than 180 House Democrats now support some form of impeachment action, according to a tally from NBC News, amounting to more than three-quarters of the Democratic caucus.

Georgia Democratic contenders for high-profile office abruptly shifted their stance, too.

Two candidates challenging Perdue - business executive Sarah Riggs Amico and Clarkston Mayor Ted Terry - endorsed impeachment after initially opposing it.

“We will still get our chance to beat him at the ballot box,” Terry said in a tweet, adding that it’s unlikely the Republican-controlled Senate will take action. “No matter what the inquiry reveals, they won’t convict. It’s in the hands of the voters!”

Democrat Jon Ossoff, who is also challenging Perdue, said “if Trump pressured a foreign power to smear his political opponent, dangling security assistance as leverage, he should be impeached.”

A fourth candidate, former Columbus Mayor Teresa Tomlinson, declared her support for impeachment proceedings shortly after entering the race.

And the impeachment debate looked likely to reframe the race for Georgia’s 7th Congressional District, which Democrat Carolyn Bourdeaux narrowly lost last year.

While several other Democratic contenders for the suburban Atlanta seat had previously endorsed the idea of impeachment, Bourdeaux had resisted, saying more investigation was needed.

Now running for the seat again, Bourdeaux told the AJC early Tuesday that she was "deeply troubled" by the most recent allegations, forcing her to reconsider her position.

"This is not a decision that I take lightly," Bourdeaux told the AJC. "But given this administration's continued stonewalling of congressional investigators, it is only through an impeachment inquiry that the facts will be fully aired."

Bourdeaux was followed by one of her primary opponents, state Sen. Zahra Karinshak.

“As a whistleblower attorney, I know that when cases like this have already been escalated this far, we've got grave cause for concern,” she said.