Omidyar’s global philanthropic organization Luminate is handling Haugen’s press and government relations in Europe, and his foundation last year gave $150,000 to Whistleblower Aid, the nonprofit organization that is providing Haugen’s legal representation and advice.

And Haugen’s top PR representative in the U.S., former Obama spokesperson Bill Burton, runs public affairs for the nonprofit Center for Humane Technology, an advocacy organization that receives funding from Omidyar. (The center is a client of Burton's firm). Haugen appeared on a Center for Humane Technology podcast earlier this month.

Another prominent tech-world figure in Haugen's camp: Harvard constitutional law professor and former Democratic presidential candidate Larry Lessig, who told POLITICO early Thursday that he is providing "limited" pro bono legal and communications work for Haugen. Lessig said he also retained Burton's firm "to provide communication advice and support."

"I am not, however, her 'main' lawyer," Lessig wrote. "That work (also pro bono to Frances) has been done by a very impressive team organized through Whistleblower Aid."

Facebook declined to comment for this article. Haugen’s representatives have not yet answered questions about how much support Omidyar and his organizations have offered directly or indirectly for her cause.

But one of Omidyar's organizations, his advocacy and investment group Omidyar Network, responded to requests for comment by pointing to a newly published blog post titled "In Support of Tech Whistleblowers Who are Holding Tech to Account."

"We are grateful to the brave people who have called out Big Tech for its bad behavior," the unbylined item reads. "They are an important part of creating systemic checks and balances for Big Tech. Because of them, policymakers are taking notice and taking action to rein in their excessive power and restore trust and balance in digital markets."

One person familiar with Luminate's strategy said Omidyar's network became involved only after Haugen went public in early October.

"I don't want to give the impression that Pierre was involved for months and secretly funding this behind the scenes," said the person, who requested anonymity to speak candidly. "It is the case that he funded lots of work around big tech and democracy — lots of different organizations for several years. And when the Haugen disclosures became public, we leaned in and said, ‘How can we help?’"

The person added that "there will be financial investments from [Omidyar's] philanthropic organizations on a forward-going basis" to support the conversation around the issues Haugen has publicized.

None of this makes Facebook an underdog, of course: Its nearly $1 trillion in market value makes it the sixth biggest company in the world by one measure, and in Washington it employs hundreds of people and has more than a dozen lobbying firms on retainer. Its CEO, Mark Zuckerberg, ranks fifth on Forbes’ list of the world’s wealthiest people.

But Omidyar is on that billionaire’s list too (at No. 83). And he has spent years channeling much of his wealth into bankrolling the fight against the big tech companies, which he criticizes as overly powerful and destructive to democracy. That includes funding groups like the anti-monopoly think tank Open Markets Institute and the digital rights group Public Knowledge.

His own network has also become increasingly involved in agitating against the major tech companies. Last year, his advocacy and investment group Omidyar Network distributed widely read papers laying out the antitrust cases against Facebook and Google. The group also hosted a series on whistleblowing in the tech industry in early February of this year, months before Haugen came forward.

Haugen, who quit her post as a Facebook product manager in May, has distinguished herself from other Silicon Valley whistleblowers with her organized PR operation. It includes a collection of top Democratic operatives including Burton — whose firm Bryson Gillette is helping to run media relations for Haugen — and Ben Scott, a former tech adviser to Hillary Clinton who now works at Luminate.

Haugen first stirred public interest as an unidentified whistleblower who had provided a trove of internal Facebook documents that formed the basis for an investigative series last month in The Wall Street Journal, then revealed her identity in a “60 Minutes” episode Oct. 3 that drew the program’s largest audience since January.

Two days later, she appeared before the Senate Commerce Committee, where she received praise from lawmakers of both parties. (Massachusetts Democrat Ed Markey lauded her as a “21st century American hero.”) Her well-curated online presence includes a personal website as well as a Twitter account that launched only this month.

On Monday, Haugen is due to testify in front of a committee in the U.K. parliament, a session to be followed by appearances next month in Belgium and France.

Despite Omidyar’s backing, Haugen’s lawyers at Whistleblower Aid have said they are struggling financially to keep up with the costs. The organization set up a GoFundMe account for Haugen that has raised about $56,000 with a goal of $100,000.

One of Haugen's other allies, Lessig, wrote in a Medium post on Oct. 11 that he is "serving in a limited capacity as pro bono counsel" to her. He described Haugen as "a woman who has risked everything to help us understand what the most powerful social media company in the world is hiding from us."

His post also defended Haugen against criticism from journalist Glenn Greenwald — who, oddly enough, was once editor of the Omidyar-funded news outlet The Intercept.

Lessig has been active in a range of causes at the intersection of tech and civil liberties, including calling for loosening of copyright and patent restrictions and support for net neutrality and open-source software.