Research project for an enterprising student

For Democrats, money or greed is the root of all evil: big corporations ripping off workers and consumers, this kind of thing. Yet when a Democrat is involved in a scandal, it's usually a financial one: William Jefferson with a freezer-full of cash, for example. For Republicans, sex is the root of all evil: gay marriage and so on. Yet when Republicans are caught with their pants down, it is usually the case that they are literally caught with their pants down: your Larry Craigs, your Mark Foleys. [Bill Clinton - the Great Triangulator - of course dabbled in both types of scandal.]

So I wonder:
- Is it true, in a statistical sense, that Republican scandals are more likely than Democratic ones to involve sex while Democratic scandals are more likely to involve money?
- By what psychological impulses are our scandal-plagued leaders driven? Is it that people who are constantly told, or constantly tell themselves, that activity X is Bad and Harmful are drawn to that activity like a moth to a flame (perhaps because they're thinking about it so much)? Or is it that those who are drawn naturally to activity X are driven by shame to pontificate against said activity?