No political party "controls the media", well actually one political party arguably does have a control on some parts of the media and more control of the narrative than the others, but not really do to backroom manipulation outside of a single network.

One political parties candidate manipulated the media to continually draw attention to themselves, or to another topic about themselves in order to avoid shining the light on another candidate, topic, or issue. They used this to such great effect that the media still runs over when this politician says fire. Heck this party even has a dedicated network just for blasting one parties propaganda, and has managed to avoid prosecution by claiming to be an "entertainment" channel.

But when I say "manipulation" I don't mean "there was a cabal in a backroom that x was going to happen". I mean this candidate played the system and won. The other political party is pretty inept at this kind of strategy, and still doesn't want to "get in the mud with the pigs" so to speak on many of these bar lowering strategies. The other party is actually really bad at any kind of grand strategy. Any vague attempt to even utilize a natural event for cynical political gain ends up blowing up in their faces, and they end up just falling into the cynical political traps of the other parties policies again and again.

There exists real media bias, but it doesn't work the way some people with too much time on their hands think it does, outside of the one channel I'm not going to name which isn't technically a news organization anyway.

CNN has a "Sensationalist Bias". When the Boston bomber crap was happening, they kept hopping around the city (when literally nothing is happening in the areas they were in) and having pundits go "OooH! is that something happening over there? What about there!" They've done this a few times. They never really make up lies they just kind of exaggerate the "possibilities" to make it sound more interesting and get people to watch.

CNN, ABC, and NBC all have a corperate bias as well. And I don't necessarily mean the "Against Bernie" kind of bias. Sometimes it appears that way, but Bernie has complained about PBS throwing "hardball" questions at him, if you've watched the interview that was never the case, and the news follows "sensationalist" stories, of which Bernie rarely had any. CNN randomly boasted about the failure that was the AOL/Time Warner merger, literally everyone else was talking about how bad that deal was for decades, Wolf Blitzer himself was talking about it at SxSW one year and how great it was. ABC stopped publication of Epstein stuff, NBC with Weinstein (money over integrity I guess).

But these organizations don't generally just "lie" about anything even in these circumstances, the omissions are meant to protect corporate interests, not project one sided bias.