(CNN) Senate investigators want to bring Paul Manafort, the former campaign chairman for President Donald Trump, in for questioning about his ties to Russia, following a new report Wednesday that says Manafort's previous work had close ties to Russian President Vladimir Putin.
Sen. Mark Warner, the top Democrat on the Senate Intelligence Committee, and Sen. Susan Collins, a Maine Republican on the committee, said they want to hear from the man who helped lead Trump to capture the Republican nomination last year.
"I definitely do have concerns about that news report," Collins told CNN's Manu Raju Wednesday, after the Associated Press reported Manafort worked for a Russian oligarch with close ties to Putin. "I don't know what the evidence is and I think it's really important that we look at the evidence and do so aggressively. We need to follow the evidence wherever it leads."
Manafort, in a statement, noted that his work for Oleg Deripaska was one decade ago and "did not involve representing political interests."
Collins wasn't the only Republican concerned about Manafort.
"I think we need to continue the investigation on it," Sen. John McCain of Arizona told CNN. "I have serious questions about some of the people in the presidential campaign. They are people with close ties to the Russians and including individuals who have made large sums of money (and) who was the Russian stooge as the President of Ukraine."
But Manafort was already an intense focus of Senate investigators even before Wednesday's report.
"This is why we have to have this investigation, why we have to talk to Mr. Manafort and a series of other individuals who have been affiliated with the Trump campaign," Warner told CNN's Erin Burnett Monday on "OutFront." "In the case of Paul Manafort, he was the actual campaign manager. We're going to need to bring him in and have that kind of conversation because there's such a cloud now that's hanging over this whole administration."
Manafort and former national security adviser Michael Flynn have garnered intense interest among lawmakers after FBI Director James Comey announced Monday that they were "investigating the nature of any links between individuals associated with the Trump campaign and the Russian government, and whether there was any coordination between the campaign and Russia's efforts."
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House investigators have expressed a strong interest in bring Flynn in for questioning -- although the leaders of the House investigation say no decisions have been made yet on who their next batch of witnesses will include.
Manafort and Flynn both played critical roles in Trump's campaign for the White House. However, as Comey was testifying at Monday's House Intelligence hearing, White House Press Secretary Sean Spicer falsely claimed that Manafort played a "very limited role" in Trump's campaign.
Anthony Scaramucci, a former top fundraiser for Trump, explained that he viewed Spicer's statement as trying to protect the president.
"I don't think we can describe Paul's role as limited," Scaramucci told CNN's Chris Cuomo on "New Day" Wednesday. "When he (Spicer) used the word limited he was basically just trying to say, 'I'm trying to shield the President from whatever could have happened if it was nefarious.' Now I believe nothing happened that was nefarious, that is just my opinion."
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