Sandra Day O’Connor? (Or Justices Ginsburg, Kagan or Sotomayor?)
Harriet Beecher Stowe? (But that’s “influence,” not “power.”)
Barbara Dianne Boxer-Feinstein?
@5. Pogo, you’re absolutely right. As long as we are not talking about who has had the most *influence*, we can put aside Oprah, Stowe and the like. (Yes, influence is a type of power, but indirectly so.)
If we’re talking about wielding raw, actual power in U.S. history, News-squeak might actually not be terribly far off the mark — but still off. I’d propose these rankings:
1. Pelosi, as austinaero says.
2. Barbara Dianne Boxer-Feinstein, as you say.
3. Sandra Day O’Connor, Ginsburg, Kagan and Sotomayor, as you say, too.
4. Hillary.
5. Eleanor Roosevelt (couldn’t legislate in her own name; plenty of power otherwise, but not as much as the women above).
Honorable mention to Mrs. Woodrow Wilson, for serving as sort of de facto president of the United States during Wilson’s incapacity.