theres definatly a bias in the media, but in this case I don't think it's so much a republican vs. democrat thing as it is a sex scandal vs. financial scandal. Sex scandals are easy for people to understand. everyone can relate to someone getting, or trying to get sex in an inaproptiate situation. Campaine finance laws are less easy to understand since they're not something that most people eer deal with. since most news is really just entretainmant they talk most about what people want to hear about, that that is the stuff they understand, sex scandals.
JUst look at the Clintons first 2 terms in office, what got more attention, the various questionable financial dealings they were inolved in, or Billy boy getting his horn honked by an intern?