[tyingq]

Geography has something to do with it. New York and Washington are liberal leaning, and that's where the origins of many of the big media companies lie.

The other piece is likely the motivation to be a journalist, as well as the college experience. Journalism programs tend to have lots of students and staff that want to be seen as "fighting for the little guy", which tends to line up more directly in a liberal context. You can see this pretty clearly by looking at the news stories that have won Pulitzers in the past.