At Morgan State on Friday, Ms. Warren revived her pitch surrounding housing, telling a story about her mother’s struggles to keep her home and contrasting that with the barriers Americans face today.

“The rules are rigged because the rich and powerful have bought and paid for too many politicians,” Ms. Warren said. “And if we dare to ask questions, they will try to divide us. Pit white working people against black and brown working people so they won’t band together and demand real change. The rich and powerful want us pointing fingers at each other so we won’t notice they are getting richer and more powerful.”

“Two sets of rules: one for the wealthy and the well-connected. And one for everybody else,” she said. “Two sets of rules: one for white families. And one for everybody else. That’s how a rigged system works. And that’s what we need to change.”

If any issue threatens to cloud the good will Ms. Warren has built among minority communities and leaders, it was her decision this year to take a DNA test to prove her claim of Native American ancestry. Ms. Warren found herself in the unusual position of being criticized by progressive leaders and Native American groups, who were angered that she seemed to embrace racial science. The issue has recently overwhelmed discussions of her presidential ambitions, but her supporters believe it can be overcome.

Derrick Johnson, the president of the NAACP, called the criticism over the DNA test issue a distraction, and said Ms. Warren deserves credit as one of the nation’s leading voices on issues of racial justice, particularly among the likely candidates for the 2020 Democratic nomination.

“There are people who have blind spots on these issues,” Mr. Johnson said. “I think many candidates have made mistakes in the past, but I don’t think she’s one of them.”