If you mean like "lizard people alien from the planet Zarkon" type alien... then I doubt it. I doubt, given the overall intelligence of the human race; that "aliens" would have to go that far to control the planet earth.
I mean, we are a species that once believed that the sun was "riding" across the sky, and that little blue people come to life and dance around children's beds while they sleep. So I dont see the need for a really inteligent being to go to such great lengths to get us.
But if Jehovah is an alien, he better hurry up and land the mother ship.... cause we are starting to figure out that dinosaurs were here a million years ago, and that the earth is a little older than six-thousand years.
Blue people. . . need I say more.... little tiny blue people, and they eat red berries and sing songs, and make smurfberry wine and..... yeah... aliens.