Dan Janison Melville. N.Y. Tuesday January 26, 2010. Daniel Janison,

Dan Janison has been a columnist at Newsday since 2007.

Long Island’s billionaire odd couple — the two big players behind financial behemoth Renaissance Technologies — keep cropping up as the Donald Trump presidency begins.

More exactly, the clashing political views of these publicity-shy associates keep surfacing separately in White House news coverage.

Last week, former President Barack Obama popped into a building in Manhattan’s Flatiron neighborhood that houses the foundation of James Simons, the Renaissance founder who remains the company’s nonexecutive chairman.

Several news organizations reported Simons is helping back Obama’s presidential library in Chicago. The 44th president received a widely publicized round of cheers and applause on the sidewalk outside as he strode to a waiting car.

The Republican side of the duo is Robert Mercer, the CEO of Renaissance, whose daughter Rebekah serves a crucial role in their conservative activism. Together they emerged as leading Trump backers after their first candidate, Ted Cruz, fizzled.

On Friday Larry Solov, CEO of the right-wing Breitbart News Network, publicly acknowledged that the Mercers are part owners of the site, but said they have no editorial role. Trump adviser Steve Bannon was an executive there.

The financial interest aroused little if any surprise in political and media circles. But it was confirmed officially with Breitbart’s application for media credentials through the Senate Daily Press Gallery.

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A spicier display, though, took place inside the East Setauket-based Renaissance company.

One internet headline among many hyperventilated: “Mutiny Breaks Out Inside The World’s Most Successful Hedge Fund Over Donald Trump.”

As first reported in The Wall Street Journal, David Magerman, a company official, was suspended after what he said was a phone confrontation with Mercer over the latter’s role in promoting Trump. Magerman’s criticism to colleagues of that role had reached Mercer, he told the newspaper.

Magerman has let his opposition to Trump policy positions be known and said he was speaking only for himself.

Remarkably, it was Democrat Simons who issued a statement in response to the story: “I have worked closely with Bob Mercer since he joined our firm almost 25 years ago.

“While our politics differ dramatically, I have always thought him to be of impeccable character.”

The Mercers’ politics have impact on other fronts. Rebekah Mercer is a trustee of and donor to the American Museum of Natural History; noticeably, the family’s private foundation also contributed millions to organizations that dispute climate change.

The Mercers also fund Cambridge Analytica, a data company that uses “psychographic” models to target individual voters based on their personality types — something that drew wide notice during the Trump campaign.

Aside from all that, Renaissance has been embroiled for years in a dispute with the IRS over certain trades that may involve billions of dollars in taxes.