Forum:Ansem vs. Xemnas

I'm sure that people have been asking this question for a long time, but it's never really been answered. Here we go, we all know that, supposedly, nobodies are stronger than heartless, however, I think (this is my opinion) that the final boss fight with Ansem was alot, and I mean ALOT harder then the one in KH2. This probably means that Xemnas and Ansem are at least equall in power, that is why I put this question here, if Xemnas and Ansem (Xehanort's heartless) were to duke it out, then who would win?