Starting in the fall, the donation will cover full tuition for medical students from families earning less than $300,000.
"What we need to know is exactly what's lurking out there," Warren said.
Former New York City Mayor Michael Bloomberg received 19% in the NPR/PBS NewsHour/Marist poll. He needed 10% to qualify.
The former New York mayor's national campaign focuses on key issues impacting black Americans.
Democratic presidential candidate Michael Bloomberg is on a two-day campaign swing through the South, but he's making news on Twitter in a tweet exchange with President Trump.
He says he has a plan to help African-American families triple their wealth in 10 years.