As much as I hate racial politics and don't wish such system to be adopted in the USA
It's institutionalised in the U.S anyway, through the legal requirement to draw black majority districts. Must admit that I do prefer the New Zealand way of dealing with this problem.
Well, even in a majority black district the white minority can vote, a white can run and (theoretically) be elected the same way a black can. The problem is with the legal requirement, but this is not comparable to an entirely racial apportionment.
Not just theoretically. Robert Brady is a white Congressman from Pennsylvania representing a Black-majority district in Philadelphia.