Political advisor Roger Stone during an interview in New York City, Feb. 28, 2017. Reuters

Roger J. Stone, a prominent though informal adviser to Donald Trump throughout the president's election campaign, doubled down on his declaration Tuesday that he did not ask a Russian agent to interfere in the November election by hacking Democratic nominee Hillary Clinton’s emails.

“I have said that repeatedly and I say that again today....It’s a witch hunt,” Stone said in an interview with "CBS This Morning.”

Read: Russian DNC Hacking Update: Roger Stone, Former Trump Adviser, Asked To Preserve Russia-Related Documents

As noted by CBS anchor Charlie Rose, Stone’s name came up 19 times throughout FBI Director James Comey’s hearing before the House Intelligence Committee Monday. In the hearing, Comey admitted that Russian President Vladimir Putin had a clear preference for Trump to take the Oval Office over Clinton, and that the bureau was indeed investigating Kremlin-sponsored cyber-attacks during the election. When asked by Rep. Adam Schiff of California if Comey knew of Stone, Comey laconically replied, "Generally, yes." As Schiff continued to press Comey about Stone and his role in the Trump campaign and with Russia, Comey expressed reservations about discussing Stone, and later would say he couldn’t discuss those involved in the ongoing investigation.

Stone, however, has admitted to making contact with Guccifer 2.0, who is accused of hacking and leaking the emails of Clinton campaign chairman John Podesta to Wikileaks. And two weeks before Podesta’s emails were released, Stone had said he “communicated” with Wikileaks founder Julian Assange, while cryptically tweeting "it will soon the Podesta's time in the barrel."

Stone maintained that he wasn’t aware that the leaks were on the horizon when he issued the tweet about Podesta and published screenshots of his direct message conversations with the Guccifer 2.0 on the far-right website InfoWars Monday showing that the only communication between the two happened six weeks after Podesta’s emails were released online.

In the interview with "CBS This Morning," Stone said he was following the Senate Intelligence Committee’s request for him to save any documents that could be related to the Trump-Russia investigation and that he was willing to testify.

Known as a "trickster," some may wonder how Stone grew to such prominence. In 2000, he played a big role to block the Florida recount in the 2000 Election. He has also written books with highly provocative titles: "The Bush Crime Family: The Inside Story of an American Dynasty," and "The Clintons' War on Women."

CNN contributor and New Yorker magazine reporter Ryan Lizza has written extensively on Stone and has described the 64-year-old as "intelligent and witty," and found his shifts from "sober analysis of politics to bizarre conspiracy theories" to be "jarring." According to reports, Stone has claimed that John F. Kennedy Jr., who died in a 1999 plane crash accident, was murdered by Bill and Hillary Clinton.

Stone has a tattoo of former President Richard Nixon on his shoulder, dresses in eccentric outfits, but often talks in a measured tone.

A member of Paul Manafort's consulting group, Stone began offering political advice to Trump in 2015 and played the role of "an outside adviser" until Trump fired him in 2016 over insurmountable differences about the direction of the campaign. A native of Westchester, New York, Stone has claimed that he has known Trump for nearly 40 years.

Despite being let go by Trump, Stone remains a steadfast supporter of the president. He backed Trump after he pushed the theory that the father of Sen. Ted Cruz of Texas, Trump's one-time opponent for the Republican presidential nomination, was somehow connected to the assassination of former President John F. Kennedy. While promoting his most recent book, Stone defended Trump's baseless claims that the president's personal offices in New York City had been bugged by former President Barack Obama, saying he too believed that the federal government placed surveillance on Trump during his presidential campaign.