WASHINGTON  – Former White House Russia adviser Fiona Hill warned House  lawmakers last month not to buy into the "fictional narrative" that it was Ukraine, not Russia, that interfered in the 2016 U.S. presidential election. 

This week, FBI Director Christopher Wray sought to debunk the theory of election meddling by Ukraine. "We have no information that indicates that Ukraine interfered with the 2016 presidential election," Wray told ABC in an interview that aired on Monday.

Yet several Republican senators, who will serve as jurors in a likely impeachment trial of President Donald Trump, have pushed the notion of Ukrainian meddling. The strategy, experts said, was to sow enough doubts about Ukraine's actions to build a case that Trump's pressure on the country stemmed from legitimate policy concerns, and was not part of a politically motivated shakedown, as Democrats contend.

"I don't think they need to have a coherent counter-narrative as much as they need to say there's reason for Trump to worry about corruption in Ukraine and that there's a long history of corruption there," said William Howell, a political scientist at the University of Chicago,

Sunday, Sen. Ted Cruz, R-Texas, told NBC's "Meet the Press" that he believed there was "considerable evidence" that "Ukraine blatantly interfered in our election."

Last month, Sen. John Kennedy, R-La. raised eyebrows when he told Fox News Sunday he didn't know whether it was Russia or Ukraine that was behind the 2016 hack of  Democratic emails. "It could also be Ukraine," Kennedy said, adding: "I'm not saying that I know one way or the other."

Though he later backtracked on the suggestion that Ukraine might have been behind the email hack, Kennedy told CNN that when it came to 2016 interference in general, "there is a lot of evidence, proven and unproven, everybody's got an opinion that Ukraine did try to interfere, along with Russia, and probably others, in the 2016 election."

Trump's dealings with Ukraine are at the center of two articles of impeachment – on abuse of power and obstruction of Congress – that were approved Friday by the House Judiciary Committee. If the articles are adopted by the Democratic-led House, as is widely expected, the matter would go to the GOP-controlled Senate for a trial in January where a two-thirds majority would be required to remove Trump from office.

Senate Majority Leader Mitch McConnell, R-Ky., told Fox News on Thursday that he will be in "total coordination" with the White House on the strategy for a trial and said he sees "no chance" the president would be removed.

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Democrats have accused Trump of withholding a meeting and military aid from Ukraine to pressure Ukraine President Volodymyr Zelensky to announce investigations that would further his political interests.

During a July 25 phone call with Zelensky, Trump asked the Ukraine president to "do us a favor." He urged Zelensky to investigate former Vice President Joe Biden, whose son Hunter once sat on the board of a Ukrainian energy company, and to look into allegations of Ukrainian election interference in 2016.

Such allegations have been pushed by Trump's personal lawyer, Rudy Giuliani, in numerous media interviews. He has spent months trying to prod Ukraine to investigate the claims and traveled to Ukraine earlier this month.

Giuliani told USA TODAY he has "compelling evidence of Ukrainians giving DNC and other [Democrats] dirty information" to influence the 2016 election.

Raising 'questions' about Ukraine 

Several Republican senators have echoed Trump in saying someone should look into claims that Kyiv interfered in the 2016 election, but most have not gone as far as the president and Giuliani in alleging a widespread effort to intervene. Instead, many GOP senators have couched their comments by saying they have "questions" about Ukraine's actions.

Sens. Lindsey Graham of South Carolina, Ron Johnson of Wisconsin and Chuck Grassley of Iowa have called for the release of records on whether former Democratic National Committee consultant Alexandra Chalupa sought damaging information from Ukraine's embassy on Paul Manafort, Trump's former campaign chairman.

“Contrary to the popular narrative in the ‘mainstream media’ that Ukrainian involvement in the 2016 election has been debunked, or ‘no evidence exists,’ there are many unanswered questions that have festered for years," Johnson said in a press release announcing the request for documents.

Republicans have argued that Trump's request for an investigation was driven by policy priorities, not by politics, and that his aim was to push Ukraine to root out corruption.

Defying intelligence: Despite Fiona Hill warning, Sen. John Kennedy says Ukraine may be behind 2016 DNC hack

But Howell criticized the willingness of Trump's allies in Congress to give credence to the theory of Ukrainian interference.

"This is a party that is caught in the thrall of Trump," Howell said, "and Trump is about to be impeached."

Karen Finney, a veteran Democratic strategist who worked on Clinton's 2016 campaign, said she believed the strategy was about confusing Americans who may not be closely following the impeachment inquiry.

"It also exemplifies the intellectually dishonest knots that Republicans are having to tie themselves into in order to defend the president," she said.

CrowdStrike theory

Trump's claims about Ukraine, now at the center of the impeachment inquiry, can be traced to special counsel Robert Mueller's investigation into Russian election meddling.

Trump has long railed against the Mueller probe, which found that Moscow waged a "sweeping and systemic" interference campaign in the 2016 presidential election. Trump has also repeatedly downplayed the U.S. intelligence community's conclusion that Russia interfered.

Intelligence agencies concluded nearly three years ago that Russian President Vladimir Putin ordered the effort to "undermine public faith in the U.S. democratic process, denigrate Secretary [Hillary] Clinton, and harm her electability and potential presidency," according to a January 2017 report from the Director of National Intelligence. The report also found the Kremlin "developed a clear preference" for Trump.

The Ukraine meddling narrative Trump has raised as early as 2017 has been spread on right-wing websites and promoted by Giuliani.

The discredited theory the president and Giuliani have repeatedly raised is the role of CrowdStrike, a private cybersecurity firm that investigated the breach of the DNC's computers in 2016. 

"I would like you to find out what happened with this whole situation with Ukraine, they say CrowdStrike...I guess you have one of your wealthy people...the server, they say Ukraine has it," Trump told Zelensky on the July 25 call.

When it investigated the DNC hack, CrowdStrike concluded the theft was the work of hackers connected to Russian intelligence services. Mueller confirmed those findings in his own probe, indicting 12 Russian military intelligence officers for the hacking scheme, which targeted the DNC and Clinton's presidential campaign as part of the Kremlin's effort to undermine the 2016 election.

But Trump has floated the possibility that Ukraine was behind the hack and framed Russia. He has also claimed – falsely – that CrowdStrike is owned by a wealthy Ukrainian who sought to cover up the crime by refusing to hand over a physical server to the FBI in its own investigation into the DNC hack. Trump has suggested that server is being concealed in Ukraine. 

He repeated the claim during a Nov. 22 Fox and Friends interview.

“And I still want to see that server. You know, the FBI has never gotten that server. That’s a big part of this whole thing. Why did they give it to a Ukrainian company?”

When pressed if he believed Ukraine was hiding a server, Trump said: "Well, that’s what the word is."

CrowdStrike is a California-based company founded by American entrepreneur George Kurtz and Dmitri Alperovitch, a Russia-born U.S. citizen who spent all of his adult life in the United States and "has no connection to Ukraine," according to the company.  

DNC Communications Director Adrienne Watson said not only was there more than one server, but none of the physical and cloud-based servers used in 2015 and 2016 are missing. 

"All of the physical servers are accounted for, and anything to suggest otherwise has no basis in fact," she said. "As we have publicly stated numerous times, we provided copies of all of the servers and related information that the FBI asked for to the FBI in 2016 and continued to cooperate with their investigations." 

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Thomas Rid, a Johns Hopkins security studies professor, said investigators aren't interested in the hardware, focusing instead on the adversaries' command and control structure and how they move files out.

"The idea that you physically had an unplugged machine that would contain a smoking gun — that idea just makes no sense."  

During the forensic investigation, CrowdStrike used a process called "imaging," which includes creating a "byte-for-byte copy of the hard drives," according to a company statement. Investigators also made copies of the hard drive's memory, capturing evidence that could be lost in a reboot while also monitoring the network's traffic.

Competing narrative 

Nina Jankowicz, a disinformation fellow at the Woodrow Wilson International Center for Scholars, said Trump's strategy in pushing the conspiracy theories on CrowdStrike is to provide a competing narrative. 

“I don’t think anybody who is spouting these theories can coherently explain them and I think that’s exactly the point. It’s to confuse people and just kind of paint Ukraine as a corrupt place that needs someone to ride in on horseback and save,” said Jankowicz, who is writing a book entitled, "How to Lose the Information War: Russia, Fake News, and the Future of Conflict."

Accusations of Ukrainian interference were floated as early as 2016 by Manafort, according to FBI testimony from Manafort's former deputy Rick Gates.

Manafort is now in prison for concealing millions of dollars he earned from a once-secret lobbying deal he had with Ukraine’s former pro-Russia president.

Giuliani has accused Ukrainian officials of releasing damaging information on Manafort to the U.S. media to tarnish the Trump campaign. 

Giuliani has questioned the credibility of the so-called "black ledger," a document obtained by Ukraine's anti-corruption bureau that showed Manafort received millions in secret cash payments from former President Viktor Yanukovych. Manafort ultimately pleaded guilty to tax fraud for illegally routing that money to offshore accounts.

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A 2017 Politico story has been widely cited by Republicans to back up their argument that Ukraine tried to help Hillary Clinton's 2016 campaign. While the story said individual Ukrainian government officials sought to undercut Trump by questioning his fitness for office, it also said there was "little evidence" of a top-down effort by Ukraine that resembled the Russian interference.

The story discussed efforts by Chalupa to seek damaging information from the Ukrainian embassy on Manafort.

“If I asked a question, they would provide guidance, or if there was someone I needed to follow up with,” Chalupa told Politico. “There were no documents given, nothing like that.”

While Chalupa described the embassy as helpful, Ukrainian embassy official Oksana Shulyar denied working with Chalupa or any reporters to get information on Trump or Manafort.

“We have never worked to research and disseminate damaging information about Donald Trump and Paul Manafort,” Shulyar said.

The DNC said it was not involved with any of her research. 

'Beyond dispute'

"The unfortunate truth is that Russia was the foreign power that systematically attacked our democratic institutions in 2016," Fiona Hill, the former Russia adviser with the White House National Security Council, told the House Intelligence Committee at a hearing last month. "It is beyond dispute, even if some of the underlying details must remain classified." 

In contrast to Trump and Giuliani, most Republican senators have steered clear of embracing the theory that the DNC hack originated in Ukraine. They also have emphasized that they do not dispute the finding that Russia interfered in the 2016 election.

But several Republican senators have reinforced the theory of Ukrainian interference by suggesting there are "unanswered questions" about Kyiv's actions that deserve to be investigated.

Sen. Mitt Romney, R-Utah who often breaks with fellow Republicans when it comes to matters involving the president, rejected the theory that Ukraine meddled in the 2016 election.

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“I know that the leaders of other countries may be pulling for one candidate or another in our elections, but it's one thing to pull for the candidate. It's another thing to interfere as Russia did.” 

John Weaver, a longtime Republican strategist and vocal Trump critic, said promoting the Ukraine meddling narrative could backfire for GOP senators at the ballot box. 

"They're looking for any way out of passing the hard judgment on a corrupt president," he said. "These actions are going to put the Senate at risk for Republicans."

But Howell, the University of Chicago political scientist, said the strategy might work to the benefit of some Republican senators, given the increasingly populist tilt of the party.

"They're raising concerns about procedure, they're raising concerns about the Democratic party and they're breathing a little bit of life into these conspiracy theories," he said.

"Populism worldwide traffics in conspiracy theories so, in that sense, I'm not sure we should be all that surprised." 

Thomas Patterson, a Harvard University professor of government and the press who has written extensively on political disinformation, said that even though experts have debunked the theories about Ukraine interference, they could have a major impact not by convincing everyone but by sowing just enough doubt with just enough people. 

“It’s just one more thing that gets out there and muddies the water and Trump is very good at muddying the waters,” he said. “You get enough people to believe it and it clouds people’s judgment.”