U.S. House Speaker Nancy Pelosi vowed Friday to protect Georgia’s most vulnerable Democratic lawmaker and flip another suburban Atlanta seat in next year’s election, even as the push for impeachment poses new challenges for her party’s candidates.

In an interview with The Atlanta Journal-Constitution’s editorial board, the California Democrat vehemently defended her recently launched inquiry against President Donald Trump, framing it in sweeping moral and ethical terms as she described the U.S. Constitution as “hanging by a thread.”

“Nobody came to Congress to impeach a president,” Pelosi said, “but we do take an oath to protect and defend our Constitution and to protect our Republic if we need it.”

Pelosi was in Atlanta to raise campaign cash for U.S. Rep. John Lewis, a close ally who announced his support for impeachment Sept. 24 in an emotional speech hours before the Californian said she'd launch the probe.

The speaker outlined House Democrats’ legislative priorities, including proposals to lower prescription drug prices, enact universal background checks for gun purchases and expand access to the voting booth. And she heaped praise on U.S. Rep. Lucy McBath, a gun control advocate whose victory in a suburban Atlanta district last year energized Democrats.

Nancy Pelosi vows to protect Lucy McBath

PHOTOS:Nancy Pelosi visits the AJC

But impeachment was never far from the forefront. Her trip to the AJC newsroom came less than 24 hours after the chairmen of three House committees released text messages showing top State Department officials urging a top aide to the Ukrainian president to investigate the Biden family in exchange for an in-person meeting with Trump.

Pelosi had for months resisted impeachment calls from some of her colleagues to shield politically vulnerable Democrats recently elected in districts won by Trump. But she changed course after details about Trump’s July 25 call with Ukrainian President Volodymyr Zelensky came to light following a complaint from an unnamed whistleblower.

“We have to make sure he’s held accountable and that he’s not above the law, and that no president coming after would ever think it’s OK to be so defiant to what the Founders had in mind,” Pelosi said of the commander in chief.

Whistleblower protection

A longtime member of the House Intelligence Committee before her ascent to the speakership, Pelosi helped write some of the country’s whistleblower laws. Protecting the Ukraine whistleblower is essential, she said, but she soon registered some uncertainty about whether his identity could be shielded from the Trump administration.

The Justice Department has gone “totally rogue,” she said, and Trump “doesn’t know the law, understand the purpose or care.”

Pelosi also rejected Trump’s demand on Friday for a formal House vote to begin an impeachment inquiry, after the president said his administration wouldn’t cooperate with the probe without a vote.

“If we want to do it, we’ll do it. If we don’t, we don’t. But we’re certainly not going to do it because of the president,” Pelosi said. “It’s wrong for a person to ask a foreign government to interfere in our election, and the president is doing it in full view — and in defiance of what our Founders had in mind.”

That drew a strong reaction from Georgia Republicans, including U.S. Rep. Doug Collins, the top-ranking GOP member of the House Judiciary Committee.

“It just goes to show you have a speaker of the House who has no consideration for fairness and due process,” he told the AJC. “That’s a blatant abuse of power and the people’s trust in the process.”

Trump described the impeachment investigation as “presidential harassment” on Twitter, and on Thursday he called on China to look into former Vice President Joe Biden and his son Hunter, who sat on the board of the Ukrainian gas company Burisma. Ukraine’s new chief prosecutor said Friday that his staff will review all previous cases involving Burisma, but so far, there has been no evidence of wrongdoing on the Bidens’ part.

Earlier Friday, Trump acknowledged that Democrats “unfortunately have the votes” to impeach him in the House. But he expressed confidence that the Senate would vote to acquit him.

“The Republicans have been very unified,” he told reporters at the White House. “This is the greatest witch hunt in the history of our country.”

‘Supernova status’

Over and over again during Friday’s AJC interview, Pelosi offered effusive praise for McBath, calling the freshman Democrat a lawmaker of “supernova status.”

“Candidates know what connection they want to know with their constituents. On gun violence, she has so much moral authority,” Pelosi said of McBath, whose teenage son was fatally shot in 2012. “She makes a room cry on this subject. She has real standing on the issue.”

Republicans have turned up the heat on McBath, who narrowly defeated U.S. Rep. Karen Handel last fall. The House GOP’s campaign arm recently launched digital ads dinging McBath on impeachment, while Republican protesters also flooded McBath’s Washington and Georgia offices this week.

McBath was not among the freshman Democrats to get in front of Pelosi on impeachment, but she later voiced cautious support for gathering more information as part of the investigation.

Pelosi urged Democrats worried about a lack of national investment in Georgia to be patient. A long list of leading state Democrats and candidates have demanded the party to begin pouring money and resources into the state now, a call that’s reached new urgency with two U.S. Senate races on the 2020 ballot along with competitive House seats.

“Suffice to say you won’t be wanting for attention,” she said of Georgia, adding that she has “no intention of losing any of my members” in 2020.

Pelosi also said she urged Democrat Stacey Abrams, last year’s runner-up for governor, to run for one of those U.S. Senate seats but that she respects her decision to expand her voting rights group’s work instead.

“I probably made it known to her that she would not just be any ordinary senator,” Pelosi said. “But she knows that. Everyone knows her vision. I saw it as an opportunity to have more minority representation in the Senate.”