Anakin does not have a father. He was conceived by midichlorians. Anakin is an archetypal heroic figure that is portrayed throughout the saga. It is this heroic arc that marks many themes in myth. Almost all the time in myths the hero will be born under extraordinary circumstances, most often a virgin birth. Lucas, being very endowed in mythic lore, certainly knows this fact which is why he devloped Anakin being conceived within a virgin birth. Lucas would destroy this mythic theme by having it be otherwise such as having Anakin actually have a father.