but since nearly all talk radio stations are conservative.

right you are there....
but add the adjective "successful" talk radio stations are conservative.

The liberal ones come and go with regularity.

That's the strength of the liberal media....
A radio program gives anyone who wants to debate the grounds to do so...
and win/get across their point, or not.

So things "do" get debated...Debate makes it fair.
vs.
the newspapers and magazines who are in fact "preaching" in a format where there can be no refute/response;
except for the comment/note that the "paper" allows in a later publication... and we know how they always pick out the toughest response supporting the other side... right....
Regards,
Blackthorn