Last summer, a staff of more than 150 people started putting together “NewsNation,” a three-hour prime-time cable news show that was billed as a throwback to the just-the-facts news programs of TV’s golden age. Unlike the prime-time shows on CNN, Fox News and MSNBC filled with partisan monologues and fiery discussions, “NewsNation” would serve up unbiased news reports in a straightforward manner.

The show made its debut in September on WGN America, a Chicago cable channel available in roughly 75 million households across the country. Its development was overseen by Sean Compton, a top executive at Nexstar Media Group, which owns WGN America. He laid out the show’s mission in a January 2020 statement: “We consistently hear from viewers who are seeking straight-ahead, unbiased news reporting that is grounded in fact, not opinion,” Mr. Compton said. “‘News Nation’ will deliver exactly that.”

Eager journalists from across the country signed on, some of them moving with their families from far away. But now, six months after its debut, “NewsNation” has abysmal ratings and disaffected staff members who say it has not lived up to Mr. Compton’s billing. In recent weeks, the news director and managing editor have resigned. Six people at the network, who spoke on the condition of anonymity to reveal internal discussions, said “NewsNation” has increasingly become a venue for right-wing views.

A Nexstar spokesman had no comment on the resignations and said that NewsNation had “a commitment to deliver unbiased news to our viewers.”

The creation of “NewsNation” was just phase one in a larger Nexstar plan to transform WGN America into an all-news channel. To mark the shift, WGN America changed its named to NewsNation on March 1.

The unrest at the channel’s flagship newscast started in earnest last month, when an industry publication reported that Bill Shine, a former Fox News co-president and Trump administration official, had been working since June as a “NewsNation” consultant. Until the article appeared, the staff did not know about his involvement, the six people said.

Several staff members said the secrecy around the hiring of Mr. Shine caused many people at “NewsNation” to question whether Mr. Compton had been sincere in his pledge to deliver “straight-ahead” coverage, or if he had planned all along to create what one person at the show called “a mini Fox News.” Mr. Compton declined to comment.

Code Name: ‘Project Neutral’

Nexstar, a public company, became the nation’s largest local TV operator in 2018, when it bought Tribune Media, the television arm of the Tribune Company, for $4.1 billion. Nexstar also gained an executive in the deal: Mr. Compton, the former head of Tribune Media’s programming department who is now the president of Nexstar’s networks division.

Mr. Compton, 47, had his first success in radio, having spent 18 years as a high-level executive at Clear Channel Radio and Premiere Radio Networks. In that job, he helped transform Sean Hannity from an Atlanta radio personality into a national star. In 2004, Mr. Compton signed Donald J. Trump to a deal that gave him a commentator role on radio shows across the country.

On Sept. 1, the day of the “NewsNation” premiere, Mr. Trump tweeted: “Good luck to Sean Compton, a winner at everything he does.” That night, the show drew an audience of 130,000 viewers, according to Nielsen. Since then the ratings have steadily dropped. Episodes in the week of Feb. 8 had an average audience of 58,000, and fell to 37,000 on March 1.

The show had the in-house code name “Project Neutral” during its planning phase. To lead the newsroom, Mr. Compton hired Jennifer Lyons and Sandy Pudar, two well-regarded veterans of the Chicago station WGN-TV.

An early warning sign for many people at the show came Sept. 22, when it broadcast a one-on-one interview with President Trump, an interview conducted just outside the White House by a “NewsNation” anchor, Joe Donlon. Mr. Compton had helped arrange the interview, as “NewsNation” noted on its website, and he accompanied the anchor to the White House.

Four “NewsNation” staff members said that, in their view, Mr. Donlon had not sufficiently challenged Mr. Trump’s false claims. And some of the anchor’s questions — he asked the president to describe his biggest accomplishment and what he enjoyed about his rallies — struck them as soft, they said. Steve Johnson, The Chicago Tribune’s TV critic, agreed, slamming Mr. Donlon’s performance in a review that called the segment “a 15-minute prime-time opportunity for the president to repeat campaign talking points without having to answer on matters of fact or logic.”

Ms. Pudar, the news director, resigned abruptly on Feb. 2. The next day, FTV Live, a cable industry website, broke the news of Mr. Shine’s involvement in “NewsNation,” further inflaming the staff, according to six people at the show.

Mr. Shine is a onetime lieutenant to Roger E. Ailes, the network’s late chairman, who was ousted in 2016 after facing accusations of sexual harassment. Mr. Shine himself was pushed out of Fox News in 2017, after he was accused in lawsuits of enabling Mr. Ailes’s behavior. The next year he joined the Trump administration as its communications head. He did not respond to requests for comment.

On Feb. 5, Mr. Compton led a meeting of key “NewsNation” staff members, about 40 people in all, according to the six people. He offered his view of the show during the meeting, saying it offered “friendly, vanilla news,” an approach, he added, that was “not working,” according to two people with knowledge of the meeting. Asked about Mr. Shine, Mr. Compton said he was “just a consultant” and urged the staff to keep an open mind about him.

Staff members were also critical of a Feb. 3 appearance by Bo Dietl, a former New York Police Department detective and conservative pundit. Mr. Dietl appeared on “NewsNation” to comment on the fatal shooting of two F.B.I. agents in Florida. After a discussion of the case, Mr. Donlon, the anchor, asked Mr. Dietl why the murder rate had risen in some American cities. “It’s very simple,” Mr. Dietl said. “It’s the political liberal Democratic values that are being forced upon us.”

The tumult at “NewsNation” continued into March, when Richard Maginn, the managing editor, resigned.

Broadcasting a Debunked Claim

In a call with investors last month, Nexstar’s chief executive, Perry A. Sook, praised “NewsNation.” “Our focus, as you know, is on being down-the-middle, unbiased, presenting both sides of an issue, balanced coverage, and I think we’ve accomplished that,” he said, citing a study conducted by Ad Fontes Media, a media watchdog organization, that in January rated “NewsNation” as neutral.

On March 1, the day that WGN America officially became NewsNation, there were changes in the prime-time lineup: “NewsNation” was cut from three hours to two and renamed “NewsNationPrime”; and Mr. Donlon was made the host of a new show, “The Donlon Report,” which allowed him to comment on the news.

Last Tuesday, election fraud was the subject of a “Donlon Report” segment. The guest was Jenna Ellis, a lawyer who made regular appearances on behalf of Mr. Trump to trumpet his debunked claims of a rigged vote. “President Trump is absolutely correct that the election results are in doubt,” she said on the show. Ms. Ellis continued in that vein, with the host interrupting her or disputing her claims only occasionally.

Toward the end, referring to Mr. Trump, Mr. Donlon asked, “Wouldn’t it help if he came out and conceded?”

“That’s not what he should be doing,” Ms. Ellis replied. “What he should be doing is exactly what he did.”