The saltwater croc named Dirty Harry made his choice Thursday in his enclosure in the northern city of Darwin when he snatched a chicken carcass dangling beneath a caricature of Gillard. Opposition leader Tony Abbott's chicken was left hanging.
Analysts say Australia's elections Saturday could be the closest contest since 1961 when a single seat decided who governed.
The crocodile used a similar technique to correctly predict that Spain would defeat the Netherlands in the World Cup last month. He joined an octopus named Paul in Germany, said to have correctly picked the winner for the final plus seven other games.