Jokes like that are always interesting. They reflect (as elsewhere mentioned) what Neil Hertz calls, "male anxiety under political pressure."
Why political? Well, oddly enough, even though Margaret Thatcher regularly got told, "Sit down, you cow," when she addressed Parliament, right-wing women--even truly monumentally crazy ones, like say Ann Coulter or Nancy reagan--never draw this sort of comment from right-wing men. One suspects that they become a combination of attractive dominatrix and mommy, but who knows?
With Senator Clinton, the political offense is most typicalloy turned toward an accusation--and it is always an accusation--of lesbianism. (As in, "How did Bill and Hillary meet? They were dating the same woman in college.") Of course, the real attack's on her feminism--but that can't be admitted, because that brings up the idea that it's a political disagreement that's at stake, and if we did that, then we can't express our hostility towards uppity women nearly as glibly and unconsciously. And anyway, the logic goes, all feminists are lesbians anyway.
Another way to put it is the stuff Freud talks about in, "The Uncanny," in "Jokes and Their Relation to the Unconscious," and in, "Psychopathology of Everyday Life." Women, being the Other, are a focus for the guy's fear and attraction--so, jokes help articulate both of these at once. Then there's this whole thing about castration anxiety--the beleaguered male subject goes back to early childhood fantasy, in which girls were seen as castrated boys, and if it can happen to them...see Freud's, "Little Hans," case study.
Jokes are also nice because they provide an alibi: anybody says anything about male anxiety/politics being connected, and you can always shoot back a) don't you have a sense of humor? b) it's just a joke, c) you libs always read too much into things...
