(Bloomberg) -- Robert Mercer, the publicity-shy hedge fund tycoon whose backing of Donald Trump earned him unwelcome fame, is stepping back into the shadows.

Mercer, 72, and his family spent just $2.9 million influencing federal elections this year, less than a third of their outlay in either 2016, when the last presidential election took place, or 2014, the year of the last midterms, according to Federal Election Commission data gathered through late December.

Combined with the demise of Mercer’s political-data firm, Cambridge Analytica, and the break with former adviser Stephen Bannon, the decline in spending suggests Mercer’s importance in conservative politics may be waning. According to two people who have worked closely with the family, Mercer and his daughter Rebekah, 45, were dismayed by the notoriety their role in Trump’s victory brought. Spokesmen for Robert and Rebekah Mercer declined to comment.

“They are very private,” said Dan Eberhart, an Arizona oil and gas investor who has backed many of the same Republican causes. “That is a negative on them getting more involved.”

Mansion March

The past two years have seen liberal protesters march on Robert Mercer’s mansion on Long Island, New York; pressure university endowments to pull money from his hedge fund, Renaissance Technologies LLC; and demand that the American Museum of Natural History strip Rebekah Mercer of her board seat. The elder Mercer stepped down from leading Renaissance last year, although he remains a senior researcher there.

The Mercers have hardly beaten a full retreat. Rebekah Mercer remains on the museum’s board and those of several influential conservative organizations, and their charitable foundation continued to shower millions of dollars on conservative causes through the end of 2017, the most recent year for which tax filings are available.

“I will not be silenced,” Rebekah Mercer declared in a speech at a charity gala in October, according to the Wall Street Journal. She spoke after receiving an award from Encounter Books, a conservative publisher, for “advancing American ideals.”

Eberhart, who runs Eberhart Capital LLC, said it’s possible that the Mercers shifted some of their spending to organizations that don’t disclose donors. He said the family is unlikely to disappear from the scene.

“Rebekah Mercer, from my understanding, is still looking for the right candidates to back, and I think you’ll still see her do fairly big things,” he said.

Losing Causes

The biggest individual political bets Mercer placed in the most recent two-year election cycle were busts. He spent $1.8 million in 2017 and 2018 supporting Kelli Ward and Chris McDaniel, U.S. Senate candidates in Arizona and Mississippi who lost to more mainstream Republicans.

Mercer’s influence in the early Trump era, and his status as a liberal bete noir, traces to his sponsorship of Bannon’s populist vision through a network of related projects. Bannon’s Breitbart News mobilized the conservative base, while the nonprofit Government Accountability Institute was tasked with uncovering corruption and feeding its research to the mainstream media. Cambridge Analytica sought to use cutting-edge science to help the family’s favored candidates target voters. Milo Yiannopoulos, an alt-right provocateur, went on a Mercer-funded college speaking tour.

That strategy seemed vindicated when Trump won in 2016, aided by Bannon and another former Mercer adviser, Kellyanne Conway, as well as data scientists at Cambridge Analytica. Breitbart rallied Trump fans, while GAI supplied an influential book critical of Hillary Clinton’s record. After the election, Bannon joined the White House as chief strategist and Rebekah Mercer worked on the transition team while forming an outside group, Making America Great, to drum up public support for the president’s policies.

The Mercer network is now in tatters. The outside group fizzled. The Mercers cut ties with Bannon after he fell out with the White House. Cambridge Analytica collapsed after revelations that the firm improperly harvested Facebook data from tens of millions of users. Yiannopoulos lost the family’s backing after disclosures he’d worked closely with white supremacists.

‘Private People’

Meanwhile, Mercer’s hedge fund pressured him to transfer ownership of Breitbart to Rebekah, and a boycott cost the news site hundreds of advertisers.

Traffic at Breitbart is down, dropping to about 9 million unique visitors last month from 23 million in November 2016, according to estimates by Comscore. In a statement, Breitbart said its own internal numbers contradict Comscore’s, without describing what those numbers show. The news site pointed to other third-party metrics showing it’s among the most popular websites in the country and that it’s consistently ranked as one of the top sites for Facebook engagements since at least 2015.

“The Mercers are private people, but they pushed their politics very publicly through toxic intermediaries like Bannon and Breitbart News,” said Matt Rivitz, co-founder of Sleeping Giants, the activist group that led the pressure campaigns against Breitbart and Renaissance. “They had a lot of influence over people, and we thought it was dangerous.”

Some parts of the Mercer portfolio remain. GAI got $1.7 million from the Mercers in 2017, according to the most recent tax filings, roughly the same as the previous four years. The family continued to bankroll Reclaim New York, a nonprofit they formed to advocate for transparency and low taxes in their home state.

The family funds those organizations and other conservative groups through its charitable foundation. According to its most recent tax return, published by Maplight.org, the foundation spent $15 million in 2017. That’s the least since 2013.

Even as they’ve curbed their political giving, the Mercers have found new causes to fund. In February, they announced a $1 million grant to a group called the Multidisciplinary Association for Psychedelic Studies. The group is studying the potential for MDMA, the psychoactive drug also known as ecstasy, to treat veterans with post-traumatic stress disorder. In a statement, Rebekah Mercer said she hoped the drug would soon be widely available for treatment. “America’s veterans,” she said, “deserve the very best care.”

To contact the reporters on this story: Zachary R. Mider in New York at zmider1@bloomberg.net;Joshua Green in Washington at jgreen120@bloomberg.net

To contact the editors responsible for this story: Robert Friedman at rfriedman5@bloomberg.net, John Voskuhl

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