The other mouse was cuter.

In the news: one article had a title that spoke of researchers' preference for male mice in drug tests, and how the results then affect human women. The title of another article described female mice as messy and hormonal. (Told you the other mouse was cuter.) Both articles described the same story. By this time, I'd like to think there's enough awareness of the effect of both titles that I shouldn't have to point it out.
More to the point - in the news: president gets shouty at a larger country that can't handle its own trash. Also in the news: dead whale with a belly full of trash found off the coast of that president's country, Turns out that - in the news: larger country is just another place that can't handle its own trash, so it ships its rotten diapers out of sight. And didn't that shout into the rain cause a stir.
The difference in mice titles was an example using a less polarizing issue, but when I watch my go-to news network or look through some convenient news aggregator, I see in that example all the more reason to ask questions about how the news is presented. Like who ends up in what timeslot, or why does one news source have almost twice the percentage of its nearest competitor on the aggregator when it has such a tendency to editorialize. (There. Better?)
The point - I don't have to vote for someone to see that there are points with which I agree, and that the courses of action proposed are likely necessary. (How's the investigation going on your end, aggregator?) I do have to keep an eye on news sources I disagree with when they display the same pattern of bias in their broadcast and print methods when it comes to political opponents.
If tough questions and seeking the truth were applied to both sides of the aisle, maybe there wouldn't be a reason to apply the term 'bias.' But seeing that that pattern has remained the same over multiple administrations in a leading example in that field and that community, I'm keeping my skepticism where it is.