If you think she only did it for the money, you haven't even 'scratched the surface'. [=there are many other factors, reasons, etc., involved]
Despite the 'surface' differences between the two candidates, they are very similar in most ways.
The tension between them is beginning to 'rise to the surface'. [=it is becoming easy to see]
(..) we were noble gold miners. Because we could have seen the light in the darkness. Gus. You were just a boy, but you remember. When we returned to the surface. There was nothing. The land was blackened, everything, everyone was gone. Dead. That was the month your father died. - I'm very sorry. (..)2012 Snow White and the Huntsman