Most politicians known for their sense of humor are good at it. Ann Richards threw one liners like a pro, and in his own ass clown way so did Franken. Problem is that each of them were telling jokes aimed at amusing one specific segment of the voters, not all Americans.
It reminds me of hearing Obama's wife on the news yesterday refer to herself as an African American first lady. To a certain crowd that may sound good but it was just wrong as hell for her to do that.