Someone who could potentially be a target of assassination would be wise to have multiple decoys. Remember the stories about all of the backup Saddam Husseins, for example?
Wicked Pilot wrote:What if it was Padme's decoy that got knocked up? That could be an interesting twist in brought forth by the EU.
Oh come now, you really think that Chosen One Jedi Anakin would mistake his lover for someone like Corde, who I must add did not look at all like Padme up close and must have been intended for only long-range viewing.
Come to think of it, maybe Keira Knightley was too busy for Episode II. She (Sabe) looks a lot like Natalie Portman/Padme. I heard that their own mothers couldn't tell the difference during the film shoot for Phantom Menace.