In answer to the initial question in this thread: By definition, yes.
Racism=power + prejudice . As in, in order to be "Racist" you have to have be of some privileged class (in this case, white skin) and have prejudicial thoughts about other people. This is Oppression Theory, which came out of the feminist movement of understanding oppression. The same formula can be applied to other privileged classe in this country - economic class, being heterosexual, being Christian, being male.
Thus, a person cannot be "racist" if they lack power and privilege. BUT this does not mean they cannot be prejudiced. We are ALL prejudiced, in some way or another.