filkertom has a
post in which he echoes
someone else in excoriating the media coverage of the Democratic candidacy for, among other things, taking cheap shots at the candidate they don't like. He mentions how, although he doesn't support that candidate, he regards this treatment as "pathetic." Another blogger I've seen (but can't at this point identify, sorry) has mentioned that the way this candidate is being treated is making him or her more sympathetic to the said person.
I suppose it's a natural human reaction. Whether we agree with someone or no, we feel the urge to defend them against unworthy attacks.
EDIT: and
ataniell93 has pointed to
this, which has the best statement of this principle I've found yet:
"what snide-and-demeaning always misses is the people on the other side of the target."