A nonprofit advocacy group that has sued several Long Island municipalities to force release of spending records has common leadership with Donald Trump’s newly reshuffled presidential campaign.

Stephen K. Bannon, who runs the anti-establishment conservative website Breitbart News, last week became the Trump campaign’s new chief executive as part of a top-level shakeup that took many by surprise.

His work with the provocative Breitbart site and past career as an investment banker has garnered the most attention, but nonprofit records show he is also the principal officer and board of directors’ vice chairman of Reclaim New York, which bills itself as a nonpartisan “center for government reform and accountability.”

Reclaim, which formed in 2013, has issued reports on the Long Island region’s high taxes and cost-of-living, and made news this summer for its pursuit of lawsuits against three towns and three school districts that it said ignored its public records request for all 2014 expenditures.

Those suits stem from the group’s “Transparency Project,” which included requests to more than 250 Long Island governments and school districts for spending records. The initiative also aims to train taxpayers on the state’s Freedom of Information Law and what records they’re entitled to.

Bannon has close ties to Rebekah Mercer, Reclaim’s chairman and treasurer. Rebekah Mercer and her father, prominent conservative donor Robert Mercer of East Setauket, were reportedly key in persuading Trump earlier this month to install Bannon atop his campaign, which at the time was facing questions about stability and direction amid sinking poll numbers.

Numerous media outlets reported that the Bannon hire was cemented after Rebekah Mercer spoke to Trump at an Aug. 13 private fundraiser at the Hamptons home of New York Jets owner Woody Johnson. The Mercers were previously top backers of Texas Sen. Ted Cruz’s presidential bid.

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Bannon and Rebekah Mercer are joined on the Reclaim board by another of Robert Mercer’s daughters, Jennifer. Bannon and Rebekah Mercer also have ties to the nonprofit Government Accountability Institute, whose president authored a recent book probing ties between Hillary Clinton’s State Department and the Clinton family charities.

A Reclaim spokesman said Tuesday that it does not comment on its board members or their activities. The group also did not directly address a question about whether Bannon or Rebekah Mercer’s national political work affected Reclaim’s mission, but provided a statement from the group’s executive director, Brandon Muir.

“New Yorkers are concerned about corruption, finding good-paying jobs, and achieving financial stability,” Muir said. “These are non-partisan issues impacting all New Yorkers. As a non-partisan, non-profit organization, our mission is guided by their needs. What we’re doing continues to gain momentum because our projects focus on empowering citizen-driven oversight that increases transparency, makes government more responsive, and makes our state more affordable.”

The group’s “Transparency Project” lawsuits targeted towns led by Republicans (Oyster Bay and Islip) and Democrats (Babylon), as well as the school districts of Elmont, Manhasset and Southampton. Oyster Bay town and the Elmont and Southampton school districts have since provided the requested documents, but Reclaim said Tuesday that Islip and Babylon towns and the Manhasset school district still have not.

“I guess I’ll wear it as a badge of honor being sued by the likes of him,” Babylon Town Supervisor Richard Schaffer, also the Suffolk Democratic chairman, said of Bannon.

Babylon has said it offered Reclaim the spending data in hard copy form, rather than the requested electronic records, but never heard back from the group. Reclaim, however, said the town first claimed that the spending data didn’t exist, then revised its response, but still has yet to meet the FOIL request.

“Babylon residents deserve a straight answer on this. They deserve a government that never provides illegal responses to FOIL requests,” Reclaim said in a statement Tuesday.