WASHINGTON — Rudy Giuliani, the president’s personal lawyer, ran a "shadow shakedown" in Ukraine, according to evidence former U.S. envoy to Ukraine Kurt Volker provided to lawmakers during more than eight hours of closed-door testimony Thursday, Rep. Eric Swalwell, D-Calif., told reporters once the deposition on Capitol Hill ended.

According to Swalwell, who attended the marathon deposition, Volker provided evidence that President Donald Trump, through Giuliani and other State Department officials, withheld aid to the country and asked Ukraine to look into former Vice President Joe Biden as well as matters related to the 2016 election.

Volker abruptly resigned last week after being named in a whistleblower complaint about a July phone call during which Trump discussed with Ukrainian President Volodymyr Zelenskiy an investigation into Biden and his son Hunter Biden. The whistleblower’s complaint alleged that Volker went to Kyiv to try to guide Ukraine officials on how to handle Trump’s demands for them to investigate the younger Biden's nearly five years as a member of the board that manages Ukraine's Burisma, a natural gas producer.

"We saw further evidence that there was a shadow shakedown going on, and that the lead, the lead deputy for the president was Rudy Giuliani. You had an experienced diplomat working for free, special envoy Mr. Volker, who, in many ways, was a front for work that was being done on the side parallel to his efforts by Rudy Giuliani,” Swalwell, a member of the House Intelligence Committee said. Volker testified to members of the House Intelligence, Oversight and Foreign Affairs committees.

Swalwell's takeaway came in stark contrast to that of his Republican colleagues.

"The facts we learned today undercut the salacious narrative that [House Intelligence Chairman] Adam Schiff is using to sell his impeachment ambitions," Reps. Jim Jordan of Ohio and Devin Nunes of California said in a joint statement following the deposition. "We hope the American people get to read the transcript of today's testimony and see the truth."

Democrats on the intelligence panel later released text messages that showed Volker and another U.S. ambassador working to persuade the Ukrainians to commit to probing Trump's opponents.

Read the text messages provided to Congress

"We have evidence of text messages between State Department officials expressing concern as early as May that there was a Giuliani-Biden thing going on that had concerned a State Department official," Swalwell said. "We have evidence that a State Department official was concerned that there was a linkage between security assistance [to Ukraine], and as he described, a domestic political campaign."

Democrats learned a lot, Swalwell said, that will advance their impeachment inquiry.

"You have more and more evidence that the president of the United States was improperly using his office, using our taxpayer dollars to leverage help from an ally, in our upcoming 2020 election," Swalwell said.

Swalwell was the only Democrat to comment on the record to reporters about the deposition. Earlier in the day, several Democrats who emerged from the meeting refused to comment on it, with Reps. Jamie Raskin of Maryland and Gerry Connolly of Virginia repeatedly telling swarms of reporters "no comment."

Republicans who participated in Thursday's meeting, which lasted into the evening, made a number of statements throughout the day, arguing Volker's testimony did not help the Democrats' case against the president.

Rep. Mike Turner of Ohio was the first GOP lawmaker to react to Volker’s testimony, saying in a statement after the first hour of questioning that he doesn’t believe that Volker "advanced [Intelligence Committee Chairman Adam] Schiff’s impeachment agenda."

"It is deeply unfortunate and regrettable that Schiff’s show trial investigation has clearly affected Volker’s ability to advance U.S. interests with Ukraine. It is my strong belief that Volker would not have been involved in nor permitted anything inappropriate, let alone illegal, in his service to our country," Turner said.

In the middle of the deposition, Reps. Jim Jordan, R-Ohio, ranking member of the Oversight panel, and Reps. Mark Meadows, R-N.C., and Lee Zeldin, R-N.Y., praised Volker as a "true professional."

Jordan said that nothing that Volker said "comports with any of the Democrats’ impeachment narrative" and he criticized Schiff’s handling of the deposition saying that Schiff wouldn’t allow State Department counsel to participate, that Schiff put limitations on staffers assisting Volker’s interview.

Later in the day, Zeldin claimed that Volker "blew a massive hole in that argument" that Trump tried to pressure the Ukrainian president to manufacture opposition research on the Bidens and said that "there was no quid pro quo" in the July phone call between the two leaders. Zeldin also argued that the president has done nothing wrong by asking Ukraine and China for help investigating the Bidens.

Schiff, meanwhile, had to leave the deposition early to fly to Chicago to deliver a lecture at Northwestern University. Before he left the Capitol, he said that he wouldn’t comment on the testimony until it was over, though he slammed the president for publicly urging China and Ukraine to investigate the Bidens earlier on Thursday.

"A president of the United States encouraging a foreign nation to interfere again to help his campaign by investigating a rival is a fundamental breach of the president's oath of office," Schiff told reporters.

Volker served as U.S. special representative to Ukraine beginning in July 2017 until his resignation. He also served as U.S. ambassador to NATO under Presidents George W. Bush and Barack Obama.