BOSTON (AP) – A genealogist in Massachusetts has uncovered evidence that Democratic U.S. Senate candidate Elizabeth Warren does have Native American heritage as she claims.

Christopher Child of the New England Historic and Genealogy Society said Monday he found an 1894 document in which Warren’s great-great-great grandmother is listed as Cherokee, which would make the Harvard Law School professor 1/32nd American Indian. Child says more research is needed.

Warren is the likely challenger to Republican U.S. Sen. Scott Brown.

Questions have arisen over whether Warren has represented herself as a minority during her academic career. She says she doesn’t remember doing so.

Warren says she wasn’t aware that Harvard had listed her as a Native American faculty member in the 1990s.

Brown’s campaign manager says the situation “raises serious questions” about Warren’s credibility.