The chief executive of a data-analytics firm that worked for President Donald Trump’s campaign reached out to WikiLeaks founder Julian Assange to offer help organizing the Hillary Clinton-related emails the website was releasing, according to a person familiar with the effort.

The outreach by the CEO of the firm, which is partly owned by a major Trump donor and has close ties to a Trump adviser, came as Mr. Trump was publicly cheering the leaks of his Democratic rival’s emails and some supporters were seeking to unearth further messages.

In an email sent in August 2016 and recently reviewed by the person, Cambridge Analytica CEO Alexander Nix told other employees at the firm and Rebekah Mercer, a top Republican donor, that he had recently reached out to Mr. Assange to offer help better indexing the messages WikiLeaks was releasing to make them more easily searchable. Those emails included a trove of messages stolen from Mrs. Clinton’s campaign chairman John Podesta’s account and from the Democratic National Committee.

In his email, Mr. Nix said he had not heard from Mr. Assange, the person said.

On Wednesday, Mr. Assange said he had rejected an approach by Mr. Nix, though he didn’t say what had been offered.

“I can confirm an approach by Cambridge Analytica [prior to November last year] and can confirm that it was rejected by WikiLeaks,” Mr. Assange wrote Wednesday on Twitter, following a Daily Beast report about the overture. He added in a second tweet: “We have confirmed the approach and rejection only. Not the subject.”


A spokesman for Cambridge Analytica didn’t respond to a request for comment. Mr. Assange didn’t respond to a request for further detail.

Mr. Nix’s email followed the Republican National Convention in July 2016, after which WikiLeaks began releasing its collection of Clinton-related emails. By Election Day, the site had released more than 50,000 emails stolen from Mr. Podesta and the DNC.

During this period, Mr. Trump praised WikiLeaks for releasing Clinton-related emails, and also sought the release of 33,000 emails from Mrs. Clinton’s State Department tenure that she had deemed personal and said she had deleted.

“Russia, if you’re listening, I hope you’re able to find the 30,000 emails that are missing,” Mr. Trump said in a late-July 2016 press conference. He later said he was joking.

Alexander Nix, chief executive of Cambridge Analytica, a data company that worked on behalf of Donald Trump’s presidential campaign. Photo: ALEX HOFFORD/EPA-EFE/REX/Shutterstock

A report by U.S. intelligence agencies in January said emails from Mr. Podesta and the DNC were stolen by Russian intelligence and given to WikiLeaks, and CIA Director Mike Pompeo has said the website is akin to a “hostile intelligence service.” Mr. Assange has said the website’s actions were important for transparency.


Mr. Trump has denied any collusion by him or his campaign with Russia and has called investigations into possible collusion during the election a “witch hunt.” Moscow has denied meddling in the election.

Cambridge Analytica began the 2016 campaign working for presidential candidate Sen. Ted Cruz (R., Texas), whose campaign paid the company $5.8 million from July 2015 through June 2016, according to campaign finance records. The Trump campaign began paying the company the following month, in July 2016, and ultimately paid it more than $5 million, much of which was for a TV ad buy that September. The Trump campaign’s first payment to the firm was July 29, 2016, the last day of the Democratic convention.

Cambridge Analytica offers analysis related to the personalities and values of voters. The firm is partly owned by billionaire Robert Mercer, Rebekah Mercer’s father, whose family began backing Mr. Trump in the election around the same time the Trump campaign hired the company.

The Mercers donated about $2 million to groups backing Mr. Trump’s campaign, according to campaign finance records. They were also instrumental in Mr. Trump’s third, and final, major campaign shake-up, when he installed Steve Bannon and Kellyanne Conway—who are both close to the Mercers—to lead the effort.


Mr. Bannon, the former White House chief strategist, sat on the board of Cambridge Analytica before entering the administration.

Mr. Nix’s outreach to Mr. Assange didn’t reference the 33,000 emails that Mrs. Clinton said were deleted from the private server she used as secretary of state, according to the person familiar with the exchange. But others close to the campaign considered or were actively searching for them.

Ms. Mercer and a person close to her had a brief conversation regarding Mrs. Clinton’s deleted emails in June 2016, a month after Mr. Cruz had dropped out of the race, the person said. The person said they discussed whether it would make sense to try to access and release those emails, but ultimately decided that looking for them would create “major legal liabilities” and would be a “terrible idea.”

That conversation took place before WikiLeaks started publishing the separate trove of Clinton-related emails in July 2016, and before the Mercers had officially begun supporting Mr. Trump’s campaign, the person said. A representative for the Mercers didn’t return a request for comment.


The Wall Street Journal previously reported that longtime Republican operative Peter W. Smith in 2016 mounted a campaign to obtain the same 33,000 emails, which he believed were stolen from Mrs. Clinton’s private server, likely by Russian hackers.

Mr. Smith told the Journal earlier this year that after vetting batches of emails offered to him by hacker groups last fall, he couldn’t be sure enough of their authenticity to leak them himself. He said he advised the hackers to provide them to WikiLeaks. WikiLeaks has never published those emails or claimed to have them. Mr. Smith died in mid-May at age 81.

Special counsel Robert Mueller is examining what if any role former Trump adviser and aide Lt. Gen. Mike Flynn may have played in Mr. Smith’s effort, as part of the larger probe into whether Trump associates colluded with Russia’s efforts to interfere in the 2016 election, the Journal reported earlier this year. A lawyer for Mr. Flynn has previously declined to comment.

The White House referred requests for comment to the Trump campaign, which issued a statement distancing itself from Cambridge Analytica but not addressing the offer to Mr. Assange.

“We as a campaign made the choice to rely on the voter data of the Republican National Committee to help elect President Donald J. Trump,” said Michael Glassner, the campaign’s executive director, in a statement. “Any claims that voter data from any other source played a key role in the victory are false.”

Corrections & Amplifications

The email that Cambridge Analytica CEO Alexander Nix sent to employees and Rebekah Mercer in which he said he had reached out to Wikileaks’ Julian Assange was written in August 2016. An earlier version of this article incorrectly stated the email was written in late July 2016. (Oct. 27, 2017)

Write to Rebecca Ballhaus at Rebecca.Ballhaus@wsj.com