Ginsburg's advocacy for women's rights propelled her beyond legal stardom and into American pop culture.
Ginsburg's advocacy of women's rights propelled her beyond legal stardom and into American pop culture.

这两种表达都可以，但略有区别。

advocacy 虽是名词，但具备动词概念，是由 advocate 变来。因此，虽然介词短语都是作定语，但区别是：

1. advocacy of women's rights：advocacy 和 women's rights 存在“动宾关系”。也就是说，“女权” 直接是“倡导的对象”。

2. advocacy for women's rights：for women's rights  是 advocacy 的“目的”。也就是说，“女权” 不直接是“倡导的对象”，而是为推动女权去做宣传工作，带有辅助倡导的意思。这种区别可以不用翻译出来，都翻译成为“对妇女权利的倡导”即可。