Buddha advised against four fruitless speculations. The fourth is:
"A first cause or origin of the world..."
He said it causes vexation in mind and madness.
A buddhist may or may not believe in god, but it is considered a question that is not really that important.
In another point of view of the question, the worshipping of god-like deities is quite widespread among Buddhists.
"A Jew who remained conservative but a practicing Buddhist."
--> A Jew can believe in both Ayin (that which is causeless and without a beginning) and Ain Soph (God, the first cause), so, yes, there is considerable overlap between Buddhism and Judiasm (which makes sense, because both Buddhism and Judiasm are both describing the same thing, it is only in their wordings that they disagree).
Christianity and Hinduism teach the same things, too.
Some forms of Buddhism teach theism, for example, Tibetan Buddhism.