'Richard Nixon Gets A Landslide Victory In 1968'.
(No, you can't change it so that Nixon's the incumbent four years early or what have you...)
Eugene McCarthy wins the 1968 Democratic nomination and subsequently gets portrayed (rightly or not) as a far-left loon by the Nixon campaign?
'AHC: Have WWI be over quickly with an Entente victory. Note: This WWI doesn't actually have to begin in 1914.'