Biden said this week that he was looking at somewhere between six and 10 candidates, a number that has fluctuated. He has indicated that he would consider several former presidential rivals (Harris, Klobuchar and Sen. Elizabeth Warren) along with other Democrats, including governors. Among them is Gov. Gretchen Whitmer of Michigan, who has been one of the most prominent governors confronting the coronavirus crisis at a moment when state leaders have become the faces of the response to the outbreak.