Stephen K. Bannon, flanked by Donald Trump’s campaign manager Kellyanne Conway and Republican National Committee Chairman Reince Priebus, celebrate as Trump speaks during his victorious election-night rally in Manhattan. (Jonathan Ernst/Reuters)

President-elect Donald Trump’s chief White House strategist, Stephen K. Bannon, accepted $376,000 in pay over four years for working 30 hours a week at a tiny tax-exempt charity in Tallahassee while also serving as the hands-on executive chairman of Breitbart News Network.

During the same four-year period, the charity paid about $1.3 million in salaries to two other journalists who said they put in 40 hours a week there while also working for the politically conservative news outlet, according to publicly available documents filed with the Internal Revenue Service.

The salary payments are one part of a close relationship between the nonprofit Government Accountability Institute, a conservative investigative research organization, and for-profit Breitbart News.

Under Bannon’s leadership, Breitbart has become the clarion of the alt-right, a term embraced by conservatives estranged from mainstream Republicans and decried by those on the left as racist and xenophobic.

The news site has produced a torrent of incendiary articles about race, immigration, liberals and moderate Republicans. It has been one of the most prominent supporters of Trump and a leading critic of Hillary Clinton.

Here's what you need to know about the man who went from Breitbart News chairman to Donald Trump’s campaign CEO before his appointment as chief White House strategist and senior counselor. (Jenny Starrs/The Washington Post)

“We think of ourselves as virulently anti-establishment, particularly ‘anti-’ the permanent political class,” Bannon told The Washington Post in January.

Trump’s selection of Bannon as a senior adviser has drawn widespread criticism from Democrats and others.

The ties between the Government Accountability Institute (GAI) and Breitbart call into question the assertions the institute made in filings to the IRS that it is an independent, nonpartisan operation, according to philanthropic specialists and former IRS officials.

Bannon launched the institute in 2012, shortly after taking the helm of Breitbart. He sought tax-exempt status from the IRS by describing the institute as an education group to help the United States and other countries maintain a “higher quality of life” through “promotion of economic freedom,” according to IRS filings.

But from its inception, the institute has been closely tied through personnel and donations to a network of nonprofit organizations that have pushed a conservative agenda, in part through highly critical reports about Clinton and the Obama administration, according to IRS filings from multiple organizations. The institute received nearly $4 million in donations between 2012 and 2014 from two conservative charities — Donors Trust and the Mercer Family Foundation.

Under federal code, tax-exempt groups known as 501(c)3 public charities must “not participate in, or intervene in [including the publishing or distributing of statements], any political campaign on behalf of [or in opposition to] any candidate for public office.”

Rob Reich, a political science professor at Stanford University who studies philanthropy, said the IRS regulations are poorly written and difficult to enforce. As a consequence, ideologically driven charities across the political spectrum are taking advantage of the agency’s minimal oversight.

“The IRS is underfunded, understaffed and inept,” he said.

A spokeswoman for Bannon did not respond to questions for this article.

GAI spokeswoman Sandy Schulz told The Post the institute “is and always has been in total compliance with all 501(c)3 rules.”

She also said that the group has a “bipartisan track record of working with top investigative units in media on award-winning reports.” In addition to Breitbart, Schulz said the institute has worked with prominent mainstream media organizations, including The Washington Post.

Post reporters have used the institute as a resource for investigative leads, but The Post has not published joint projects with the charity.

But the charity’s affiliation with conservative groups is clear in its IRS filings.

The institute’s board of directors included Rebekah Mercer, director of the conservative family charity, who has become an influential adviser to Bannon and Trump, disclosure forms show. Mercer’s father, Robert Mercer, a hedge fund billionaire, is a well-known conservative donor. Rebekah Mercer could not be reached for comment.

Institute director Ron Robinson is the longtime president of Young America’s Foundation, a charity that is “committed to ensuring that increasing numbers of young Americans understand and are inspired by the ideas of individual freedom, a strong national defense, free enterprise, and traditional values.”

Its motto: “The Conservative Movement Starts Here.”

Robinson did not respond to a request for an interview.

The institute is small, with typically 20 or fewer employees and interns, according to documents filed with the IRS and interviews with former institute workers who spoke on the condition of anonymity because they fear reprisal.

But it paid its leaders well.

“They all work long hours,” Schulz said.

As the institute’s co-founder and executive chairman, Bannon received $81,000 to $100,000 a year for working 30 hours a week from 2012 through 2015. At the same time, he oversaw Breitbart News as executive chairman from offices in Washington and Los Angeles.

In 2011, Bannon joined Breitbart’s board and ascended to the leadership position after the news site’s eponymous owner, Andrew Breitbart, died of heart failure at 43 in 2012.

Bannon immediately set about expanding Breitbart’s reach and influence, openly touting its ideological mission. He had conference calls twice daily with reporters, with an emphasis on stories about immigration, refugees and crime that Bannon thought the mainstream media was ignoring.

Bannon stepped down from the institute in August, spokeswoman Schulz said. The charity’s financial disclosure documents are not available for 2016. She did not respond to questions about Bannon.

The institute’s communications strategist, Wynton Hall, a conservative writer and activist, received $600,000 in pay from 2012 through 2015.

In its filings, the institute told the IRS that Hall worked 40 hours a week there. He has worked at Breitbart as a writer and social-media chief, and in 2013 was promoted to managing editor. Hall did not respond to a request for comment.

In announcing Hall’s elevation to managing editor, Bannon described Breitbart at the time as an around-the-clock operation.

“Having a 24/7 editorial team focused on the site, coupled with senior editors generating content, allows us to continue Andrew’s legacy of waging ‘fights that matter,’ ” Bannon said.

The institute’s president, secretary and treasurer is Peter Schweizer, a prominent conservative writer and at-large editor for Breitbart. He received $778,000 in salary from the institute for 2012 through 2015, the IRS filings show.

The institute said Schweizer worked 40 hours a week. At the same time, he was researching and writing “Clinton Cash: The Untold Story of How and Why Foreign Governments and Businesses Helped Make Bill and Hillary Rich,” published by HarperCollins in April 2015. The paperback version of the book hit the New York Times bestseller list in August, during the final stretch of the presidential campaign.

In the book’s acknowledgments, Schweizer cited the institute and said, “I want to say a special thanks to those who have supported our research over the past couple of years, which has offended both Republicans and Democrats in Washington.”

Schweizer did not respond to a request for an interview but provided a statement through institute spokeswoman Schulz defending the organization as nonpartisan.

“The Government Accountability Institute’s [GAI] track record investigating Republicans is clear and undeniable. Republicans like John Boehner, Spencer Bachus, Roy Blunt, Dennis Hastert, Ron Paul, Jeb Bush, Saxby Chambliss, Ander Crenshaw, Ray LaHood, Richard Lugar, Marco Rubio, Jerry Lewis, Bill Young, Dave Camp, Tom DeLay, and the National Republican Congressional Committee have all been the subjects of serious GAI reports and books,” the statement said.

“As the NYT editorial board wrote, ‘aside from Mr. Schweizer, the push to limit and disclose donations has come almost entirely from the left.’ The GAI pursues the facts, regardless of party.”

Schulz did not respond to questions about the financial and editorial links between the institute and Breitbart. The institute disclosed that it bought more than $200,000 in advertising at the Breitbart site from 2013 to 2015, IRS filings show.

Breitbart and the institute continue to promote “Clinton Cash.”

The charity’s website includes an advertisement for the book, with links to another for-profit promotional website where visitors can buy it.

“Meticulously researched and scrupulously sourced, filled with headline-making revelations, ‘Clinton Cash’ raises serious questions of judgment, of possible indebtedness to an array of foreign interests, and ultimately, of fitness for high public office,” the promotional material says.

The institute’s vice president is a Tallahassee lawyer, Stuart Christmas. He said he worked work from 25 to 40 hours a week and accepted more than $480,000 in salary over four years.

Christmas did not return repeated phones calls from The Post.

In documents filed with charity regulators in New York, the institute listed an address that has also been used by Christmas’s law firm. In filings with federal regulators, the institute uses a post office box in Tallahassee as its address.

The IRS has been exceedingly cautious about enforcing charity regulations relating to political activity since the 2013 disclosure that some IRS employees focused on tea party groups seeking tax-exempt status, triggering a fierce conservative backlash.

Republican lawmakers launched investigations and publicly lambasted the IRS. Breitbart News was among the critics.

Hall, the Government Accountability Institute’s communications strategist, wrote a 2013 Breitbart article that described the enforcement effort as a “scheme to target the tea party and conservative groups.”

In 2016, as the presidential campaign heated up, Schweizer and his institute colleagues focused less critical attention on Trump than Clinton. The institute’s website displays no investigative reports on Trump this year but two on Clinton.

One report released in the summer focused on the private email server that the Democratic presidential nominee used during her tenure as secretary of state and the deletion of thousands of her emails that she deemed private.

“Research by the Government Accountability Institute shows that Secretary Clinton’s email record contains anomalous patterns in her email history,” the report says.

Schweizer also showed a proclivity for criticizing Clinton over Trump in his articles for Breitbart.

Before the election, he wrote one Breitbart piece about Trump, with the headline “Donald Trump’s Hypocrisies.”

“Having written quite a bit on the question of hypocrisy,” Schweizer wrote in February, “I can say that there are often yawning gaps between what Trump criticizes others for and what he himself does.”

He wrote more than a dozen stories critical of Clinton, according to a search of the Breitbart website.

“Will the Clintons Finally Be Held Accountable for Their Corruption? Maybe,” says the headline of a Schweizer story in Breitbart in January.

Alice Crites and John Sullivan contributed to this report.