Dirty tricks, old school. BBC News has an interesting article that places the current Presidential campaigns and the attendant dirty tricks in historical perspective. My favourites come from one of the earlier of the contests that they write about, John Quincy Adams vs Andrew Jackson. From a pamphlet by Adams' supporters:

General Jackson's mother was a common prostitute brought to this country by British solders! She afterwards married a mulatto man with whom she had several children of which number General Jackson is one!!

Much more mean spirited than sending pizzas and limos to your opponent (Mitchell vs Muskie, Democratic primaries, 1968) or going on about someone not turning up for National Guard duty. (It's the National Guard for crissakes. It's not like he refused to go over the top at the Somme or something. The issue shouldn't be what he didn't do back then, but the lies he is telling now.)