This sounds very,
very familiar.
The True Master.
*flashes suspicious glance in
Boromir's direction*
Anyway, my opinion: yes and no.
Sauron and the Ring are one, technically one cannot master the other. Yet they are seperate physically, so the possibility seems there.
Sauron more or less requires the Ring to function. If it is destroyed, he is as good as gone. As long as it survives, he does. Seems like the Ring is more pertinent, yes? Yet without Sauron's will inside the Ring, it would be a simple gold band. So Sauron is also essential to the pair. And, although Sauron wants the Ring badly, the Ring also desires to be in the hands of it's maker. Each requires and needs the opposite.
The pair are masters of each other.