Exactly this has happened to Aussie comedian Mick Molloy. An aspiring politician called Nicole Cornes was deeply offended by one of his gags and has taken him to court.
The whole thing seems very strange. Firstly, he's a comedian. By definition his material is not meant to be taken seriously. Also, the show in question was broadcast over two years ago. If she'd done nothing, the offending joke would have been long forgotten. (Actually, I think it would have been forgotten the next day!) It's even stranger that she was entering politics. In that profession, a thick skin is not only an asset, it's mandatory!