Apparently Fox got hammered after the debate due to their obvious anti-Trump bias, and the backlash was way worse than they anticipated. Here is the story, and this article by the same author has even more juicy details.
From the first link…
This morning, Trump tweeted that Ailes called to assure him that Fox will cover him “fairly” going forward. According to two high-level Fox sources, Ailes’s diplomacy was the result of increasing concern inside Fox News that Trump could damage the network. Immediately following Thursday’s debate, Fox was deluged with pro-Trump emails. The chatter on Twitter was equally in Trump’s favor. “In the beginning, virtually 100 percent of the emails were against Megyn Kelly,” one Fox source, who was briefed on the situation, told me. “Roger was not happy. Most of the Fox viewers were taking Trump’s side.”
More @ Conservative Heritage News