In the Terry Pratchett book "Small Gods", it is stated that the power of a god/goddess is directly influenced by the number of believers a god has. Therefore, when comparing god-like beings, we should take into account thee number of believers they have. When the Christian God is being compared to another god, Jehovah gets a belief sum of roughly 2 billion (not counting Jews and Muslims, although they technically worship the same god) When Jews and Muslims are factored in to Jehovah's Belief Sum (or BS. I know this group's athiests will have no compunctions about matching Jehovah and BS

God gets a rating of roughly 3 billion (I don't know how many Jews there are worldwide) Compare this to say, Om. IIRC, Omnia comprises some 2 million citizens. Therefore, in a case of God vs. Om, God wins.
Now, for someone to factor into a god's BS, they have to believe that god exists. They don't necessarily have to worship that god. Take Q. Picard believes Q exists, even though he doesn't worship him.
An outright worshipper of a god adds twice as much to a BS, on the grounds that their belief is stronger.
I will change this as necessary.