In Dubuque, Iowa, in August, he answered a reporter asking about his tacit criticism of Hillary Clinton’s benefiting from “super PACs” by saying: “The corporate media talks about all kinds of issues except the most important issues. O.K.?” In December, his campaign demanded that the “corporate network news” grant him as much coverage as it does Mrs. Clinton (the “Bernie blackout,” they called it). And in his speech on the night of the Iowa caucuses, he directed familiar contempt to “all of my critics out there in The Wall Street Journal and The Washington Post and in corporate America, wherever you may be.”

The Clinton campaign, however, argues that Mr. Sanders has benefited from the superficial horse-race journalism he scorns, and that coverage has largely focused on his avuncular style and cross-generational appeal rather than thorough inspections of his proposals or record. In the Vermont senator’s continual discrediting of the news media, the Clinton campaign sees an effort to inoculate himself from critical coverage.

“He should get more scrutiny,” said Joel Benenson, Mrs. Clinton’s pollster. In admiring words rarely uttered by a political operative, he added: “You guys in the media are the referees. You are independent. You aren’t partisan.”

The paradox for reporters covering the Democratic presidential race is that the Sanders campaign remains far more accessible to the press than Mrs. Clinton, whose wariness of the news media, after decades in the center of the public eye, is well established. Though he declined to comment for this article, Mr. Sanders often speaks with reporters on the phone or on his campaign plane. He has become a Sunday morning show regular, and last weekend he entered the belly of the beast for his debut appearance as a presidential candidate on “Fox News Sunday.”

At the end of the interview, the show’s host, Chris Wallace, told Mr. Sanders, “I hope you feel that you haven’t been mistreated,” and asked if he would be willing to participate in a Democratic debate on the network. Mr. Sanders said that if the rules were fair and the Democratic National Committee endorsed it, “I would have no objection.”

But throughout his career, Mr. Sanders has found most all news media, even public television, objectionable.