The longtime GOP strategist Roger Stone is seeking donations to his legal defense fund as the special counsel Robert Mueller zeroes in on him.

Stone sent a photo to Business Insider early Saturday that appeared to be a play on Nike's recent ad campaign featuring NFL player Colin Kaepernick. The photo featured a link to Stone's new legal defense fund.

Stone, who is an informal adviser to President Donald Trump, also recently told Business Insider that he is looking to expand his legal team as the Russia probe heats up and will announce the new additions shortly.

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The longtime GOP strategist Roger Stone is asking for donations to his legal defense fund as the special counsel Robert Mueller's Russia investigation heats up.

Early Saturday, he sent a photo to Business Insider that appears to be a play on Nike's recent ad campaign featuring NFL player Colin Kaepernick.

"Believe in something. Even if it means Mueller will frame you," said a caption overlaying a black and white photo of Stone. Another caption at the bottom of the photo read, "Just do it," and featured a link to Stone's new legal defense fund.

Stone sent this meme to Business Insider in a text message. Roger Stone

Stone has been in Mueller's crosshairs since the early stages of the Russia investigation, which is probing Russia's interference in the 2016 election and whether members of President Donald Trump's campaign colluded with Moscow to tilt the race in his favor.

Stone is currently represented by two lawyers in Florida, but he recently told Business Insider that he is looking to expand his legal team as Mueller closes in on him. He added that he will announce the new additions shortly.

The special counsel has called over half a dozen of Stone's associates to testify in the Russia probe so far.

Most recently, the radio host Randy Credico testified before a grand jury in Washington, DC, on Friday. The far-right political commentator Jerome Corsi, one of Stone's close friends, was also subpoenaed to testify in connection to the investigation, but his lawyer said Friday that Corsi would not appear before the grand jury.

Mueller's focus on the two men, as well as other Stone associates, indicates that he is homing in on links between Stone and the radical pro-transparency group WikiLeaks.

WikiLeaks published thousands of hacked emails from the Democratic National Committee and the Hillary Clinton campaign at the height of the 2016 election. The US intelligence community believes the breaches and subsequent dissemination of emails were carried out on the Kremlin's orders.

When prosecutors indicted 12 Russian intelligence officers in July on conspiracy and hacking charges, they referenced WikiLeaks — though not by name — as the Russians' conduit to release stolen documents via the hacker Guccifer 2.0, who is believed to be a front for Russian military intelligence.

Stone is known to have been in direct communication with WikiLeaks and Guccifer 2.0 during the election.

He also said he has communicated indirectly with WikiLeaks founder Julian Assange in the past through Credico. Credico denies the claim, and he said following his grand jury appearance Friday that prosecutors had demonstrated interest in Stone's statement.

When he was an informal adviser to Trump during the campaign, Stone sent out several tweets in the summer of 2016 that raised questions about whether he had prior knowledge of WikiLeaks' plans to publish the hacked emails.

In one tweet that drew increased scrutiny, Stone wrote on August 21, 2016, "Trust me, it will soon [be] Podesta's time in the barrel," an apparent reference to Clinton campaign manager John Podesta.

WikiLeaks published a batch of hacked emails from Podesta's account days later.

Stone denies knowing about the document dump in advance.

"Mr. Mueller has no evidence whatsoever of Russian collusion, WikiLeaks collaboration, advance notice of the acquisition and publication of John Podesta's emails or any other illegal activity pertaining to the 2016 election, because none exists," he said in a statement to Business Insider.