I've been thinking about how to model ideological media under a value competition framework. My initial take: Ideological bias in the media is a good thing under certain conditions. It may generate higher levels of work effort by those in the media. Also, it may help a populace with insufficient devotion to values as opposed to group-based preferences to adopt ideological beliefs that cut against group interest in some cases and that motivate activism in others; a basic proposition of the VC framework is that in a populace with such cross-cutting values, politicians have better incentives to avoid beggar-thy-neighbor, group-based policies.
In thinking about how biased media with better information than the populace about candidates and policies would be expected to cover politicians from their side and the other side, I reached a conclusion that was different from my unconsidered sense that ideological media in a situation in which the other side lacks media of its own would simply cheer on their side's champions and flay the other side's. The intuition behind the conclusion: To maximize the chances of your side's winning, you as the ideological media want to persuade your readers/watchers/listeners that your side has better incentives than the other side to pursue policies in the interests of society rather than policies dictated by ideology or group interest. The best way to do that is to draw on your superior information to be sincerely critical of your side's policies and candidates, from which voters will rationally conclude that your side's politicians are being monitored at least reasonably adequately. By contrast, you should send no reliable signals of candidate or policy quality about the other side. Faced with a choice between one side with politicians and policies about which the media sends at least partly reliable quality signals and another side about which no such signals are sent, rational voters will all else equal favor the side disciplined by quality signals. Uncontested ideological media would thus be expected not to exalt their side's politicians and policies and to trash the other side's, but to be discriminating about their side and indiscriminate about the other side.