I don't know which paragraph in Jonathan Chait's New York magazine essay, “The Only Problem in American Politics is the Republican Party,” to highlight, since they're all so relevant, and explain so much of the world. 

This gets at it:

Whatever interest liberals may have in finding congenial media, they don't dismiss the mainstream media out of hand in the way conservatives have been trained over decades to do. When the conservative news media criticizes Republicans, it is almost always to play the role of ideological enforcer, attacking them for their lack of fervor. One party has a media ecosystem that serves as a guardrail, and the other has one that serves only as an accelerant.

This is probably closer to it:

Democratic politicians need to please a news media that is open to contrary facts and willing — and arguably eager — to hold them accountable. The mainstream media have have its liberal biases, but it also misses the other way — see the Times' disastrously wrong report, a week before the election, that the FBI saw no links between the Trump campaign and Russia and no intention by Russia to help Trump. One cannot imagine Fox News publishing an equivalently wrong story against the Republican Party's interests — its errors all run in the same direction.

The sad part is the mainstream news media—New York Times, NPR—still doesn't get it. They keep trying to find a middle ground as the Republican party moves gleefully, dangerously right. I think a lot of mainstream journalists think the truth lies on the other side of whatever the public image is, so they search for the lurid in Barack Obama and the respectable in Donald Trump. They keep searching for Trump's “pivot.” They think in contrarian terms. Peter Baker's recent “news analysis” in the Times, saying Trump upends “150 years of two-party rule,” calling him an independent and (in one subhed) a “Lone Ranger,” is an example. Lone Ranger? Jesus Christ. What's the difference? What's the fucking difference? The Lone Ranger is a hero for children in the 1930s and '50s, and Donald Trump is a present-day solipsistic monster, and the two have nothing to do with each other. Journalists, go back to your Orwell: “To see what is in front of one's nose needs a constant struggle.” I.e., Quit trying to be so fucking clever. Quit damning both houses in order to try to appear objective. Here's your question: What is it? Here's another: How do they differ? Go from there.