The New York Times and MSNBC are bringing in right-wing commentators to join their center-right supporters of Clinton and co. They have a few progressive commentators, but no one that explicitly supports Sanders.

The idea of the "Liberal media" is a right-wing fabrication. They call centrist politicians and media "Liberal" to make some not-so-extreme right-wing views appear to be "the center". Politicians like Sanders, that most Americans agree with, they call "extreme".