Anyone who uses racist slurs to denigrate a black person is a racist. Some of them may be relatively soft, casual or conflicted racists, but they are all racists. No exceptions, but at least the condition is not necessarily permanent. Some racists, particularly the unthinking, casual, kind, develop a sense of human decency over time.
It is always interesting though the number of people who seem to have such strong motivation to find some loophole that would allow people to engage in racist speech and behaviour while avoiding having the tag racist pinned to them. Some people just go around calling work colleagues who annoy them "dirty negroes", it doesn't mean that they are racists! How dare you imply such a thing!