How do politicians and the media benefit one another in this political system?

Politicians and the media work closely in an effort to benefit one another and control the messages that are distributed to the masses. Politicians go on tv shows to boost ratings when needed and in return the media helps the politicians they like to get re-elected by presenting a disproportional degree of beneficial coverage on that candidate and their initiatives. CNN is primarily responsible for spreading messages for liberal politicians, while Fox is primarily responsible for right-wing messages. This balance is carefully maintained in an effort to control public opinion. Even though the stations pretend to attack one another's motives, they are actually working for the same group of power brokers in the beltway.