President Donald Trump’s growing feud with Steve Bannon is threatening the former White House strategist’s leadership of the conservative Breitbart News website and upending Mr. Bannon’s plans to wage “war” on party incumbents he deemed insufficiently loyal to the White House agenda.
Mr. Bannon’s longtime benefactors, billionaires Robert Mercer and his daughter Rebekah Mercer, are actively distancing from him even before the expected release this week of a book that has roiled Messrs. Trump and Bannon’s relationship, according to two people close to the Mercers.
The Mercer Family recently dumped the leaker known as Sloppy Steve Bannon. Smart!
— Donald J. Trump (@realDonaldTrump) January 5, 2018
They and other Breitbart News Network LLC board members on Thursday were debating whether to oust Mr. Bannon as chairman, with many supportive of the move, according to a person familiar with the exchanges. Among the considerations are Breitbart’s contractual relationships with other entities, including Sirius XM radio, that involve Mr. Bannon.
Staffers at Breitbart, which Mr. Bannon has called his “killing machine,” described a “chaotic” day at the company, with writers—many personally recruited by Mr. Bannon—wondering whether he would last the day.
Mr. Trump said Mr. Bannon has “lost his mind” and that he has “nothing to do with me or my presidency,” a response to Mr. Bannon’s numerous incendiary comments—including insults about the…