What's the difference between having a preferred "type" in a romantic partner and having a "fetish"?

In the recent question about Japanese women several people referred to some men having an “Asian fetish.” I have one relative who was drawn mainly to fair skinned redheads and another who did like Asian women.

I wouldn’t have described either of them as having a fetish for that type so I am wondering where people draw the line.

I don’t have a dog in this fight (not my type!) but I thought it could make for a fun discussion.