In the 1936 election, Roosevelt claimed that 85 percent of the newspapers were against him. In the standard work on the subject, historian Graham J. White finds that the actual percentage was much lower and the print press generally gave FDR balanced news coverage, but most editorialists and columnists were indeed opposed to the administration. Convinced that the media were out to get him, Roosevelt warned in 1938 that "our newspapers cannot be edited in the interests of the general public, from the counting room. And I wish we could have a national symposium on that question, particularly in relation to the freedom of the press. How many bogies are conjured up by invoking that greatly overworked phrase?"
Roosevelt's relationship with radio was warmer. The key distinction was that broadcasters operated in an entirely different political context: Thanks to federal rules and administrators, they had to tread much more lightly than newspapers did. At its inception in 1934, the Federal Communications Commission (FCC) reduced the license renewal period for stations from three years to only six months. Meanwhile, Roosevelt tapped Herbert L. Pettey as secretary of the FCC (and its predecessor, the Federal Radio Commission). Pettey had overseen radio for Roosevelt in the 1932 campaign. After his appointment, he worked in tandem with the Democratic National Committee to handle "radio matters" with both the networks and local stations.
It did not take long for broadcasters to get the message. NBC, for example, announced that it was limiting broadcasts "contrary to the policies of the United States government." CBS Vice President Henry A. Bellows said that "no broadcast would be permitted over the Columbia Broadcasting System that in any way was critical of any policy of the Administration." He elaborated "that the Columbia system was at the disposal of President Roosevelt and his administration and they would permit no broadcast that did not have his approval." Local station owners and network executives alike took it for granted, as Editor and Publisher observed, that each station had "to dance to Government tunes because it is under Government license." Some dissident radio commentators, such as Father Charles Coughlin and Boake Carter, gained wide audiences. But radio as a whole was firmly pro-Roosevelt--and both Coughlin and Cockran were eventually forced off the air for pushing the envelope too far.
This is from David Beito, "FDR's War Against the Press," Reason, May 2017. The whole piece is excellent. I knew some of this but I had no idea of the extent of it. Also, I knew from Robert Caro's work on LBJ that Hugo Black carried water for FDR, but, again, I had no idea of the extent.