Sen. Lindsey GrahamLindsey Olin GrahamJohn Feehery: Censure could give Democrats a way out of no-win impeachmentGraham, Van Hollen warn Pompeo that ‘patience’ on Turkey sanctions ‘has long expired’Impeachment inquiry enters critical new phaseMORE (R-S.C.) on Tuesday said he’s “1,000 percent confident” Russia was responsible for hacking the Democratic National Committee (DNC) as part of an effort to interfere in the 2016 election, dismissing the theory that Ukraine played a role in the breach.

The comments from Graham come amid a House impeachment inquiry into President TrumpDonald John TrumpJustice Dept releases another round of summaries from Mueller probeNorth Dakota company gets 0M border wall contract after support from TrumpFox’s Cavuto reads mean letters urging him to stay away after Trump criticismMORE’s dealings with Ukraine and whether he conditioned military aid on the country opening investigations that benefited him politically.

Trump and some of his GOP supporters in Congress have pushed a conspiracy theory that Ukraine tried to meddle in the 2016 election to help Democratic nominee Hillary ClintonHillary Diane Rodham ClintonSenate Intel found no evidence of 2016 Ukrainian interference: report Kennedy doubles down on alleged Ukraine meddling amid criticismTrump campaign steps up attacks on BidenMORE.

“It was the Russians. I’m 1,000% confident that the hack of the DNC was by Russian operatives, no one else,” Graham told reporters on Capitol Hill. 

“I have no evidence (Ukraine) did. Russia stole the emails, not the Ukraine,” he added. 

Asked about whether Trump was muddying his defense by pushing the claim, Graham said he thinks it’s “always wrong to say things that can’t be proven.”

The conspiracy theory that Ukraine hacked the DNC has gained increased attention in recent months. Trump referenced the claim during a July 25 phone call with the Ukrainian president that is now at the heart of House Democrats’ impeachment inquiry. 

In the call, Trump urged Volodymyr Zelensky to look into CrowdStrike, an internet security company that initially examined the breach of the DNC servers in 2016. 

Tom Bossert, a former homeland security adviser in the Trump administration, said in late September that the allegation was a “completely debunked” conspiracy theory. Fiona Hill, a former top Russia analyst for the White House, also testified last month that the idea that Ukraine interfered in the election is a “fictional narrative that has been perpetrated and propagated by the Russian security services themselves.” 

Trump has, meanwhile, continued to float the allegation, claiming in an appearance on Fox News last month that officials gave a DNC server to “CrowdStrike, which is a company owned by a very wealthy Ukrainian.” CrowdStrike is a U.S.-based company. 

Graham, an outspoken Trump supporter, said that the unfounded allegation likely stems from confusion over media reports about Ukrainian officials’ communications with the DNC. Though he said “nobody from the intelligence community has ever told me that that happened.”

While the South Carolina senator pushed back against Trump’s unsubstantiated claims, Graham has repeatedly voiced support for the president amid the impeachment inquiry.