Warren has responded to Brown's ad with her own 30-second video, speaking directly to the camera with this message: "I never asked for and never got any benefit because of my heritage."
A good many voters in the state agree with the view that she didn't benefit. Others disagree, however. And Warren's critics argue the important question is not whether she benefited, but whether career advancement was her motive.
Here is what has come out so far through the political campaigns and through media reports.
1. Warren listed herself as a minority. The Association of American Law Schools (AALS) directory included, as of its 1986-87 edition, a list of "minority law teachers." Warren, then at the University of Texas, was on the list. Moving to the University of Pennsylvania the next year, she continued to be on the minority list through the directory's 1994-95 edition. The later years of her listing coincided with her recruitment by Harvard Law School, initially as a visiting professor.
2. Harvard was under pressure to diversify its faculty. Warren's listing came at a time when law schools around the country faced pressure from minority advocates to show greater diversity on their faculty, in race as well as gender. In one 1992 incident, students staged a sit-in in the office of the Law School dean to push for greater faculty diversity.