In his new biography of Fox News chief Roger Ailes, New York magazine writer Gabriel Sherman reports that Ailes unsuccessfully tried to recruit Rush Limbaugh to host a show on the network.

Sherman explains that when Fox's ratings dominance started to show signs of slipping in 2006 surrounding the GOP's drubbing in that year's midterm elections, Ailes reportedly tried to convince Limbaugh to start his own Fox show: 

For almost a decade, Ailes had played a role in driving the news; now he was captive to it, with few apparent options to reverse the ratings trend, and at Fox there were incipient signs of panic. “We had the concern that the slide could turn into a freefall,” a producer said. Ailes's plans to turn the ship around were running aground. He made an aggressive bid to convince his old friend Rush Limbaugh to come to Fox. Limbaugh turned him down flat. “Rush was kind of laughing at the whole thing,” a Limbaugh friend who spoke with him during the talks recalled. “He said, 'Roger is really trying to get me to come back.' And Rush was like, 'Why would I do this?'” [The Loudest Voice in the Room, pg 312]

Ailes had previously served as the executive producer of Limbaugh's syndicated TV show in the 90s.

According to Sherman, Fox wasn't the only network to pursue Limbaugh in a desperate bid to save flagging ratings. Sherman writes that in 2001, concerned with Fox's ascendancy, then-CNN chief Walter Isaacson tried to tack the network to the right, including by courting Limbaugh:

Both CNN and MSNBC were under pressure from their corporate parents to catch up to Fox. An obvious strategy was to become more conservative. In the summer of 2001, CNN chief Walter Isaacon courted Republicans. He traveled to Washington for private meetings with Senate majority leader Trent Lott and House speaker Dennis Hastert. He also wooed Rush Limbaugh and offered him a show. [The Loudest Voice in the Room, pg 276-277]