Those responsibilities will be even more weighty as the country combats the coronavirus pandemic; endures the worst economic crisis since the Great Depression; and reckons with questions of race, policing, and discrimination reignited by the killing of George Floyd in Minneapolis. “Joe Biden’s vice president will most likely be the most powerful vice president in history because the trend is toward more powerful vice presidents, Joe Biden knows the value of having a vice president with lots of responsibility, and Joe Biden is going to inherit an epic disaster,” Dan Pfeiffer, a former Obama senior adviser and co-host of Pod Save America, told me.

At the same time, with Biden planning to serve as a “transition candidate” for a new wave of younger and more racially diverse Democratic politicians, she’s also likely to face a degree of attention and scrutiny that few vice presidents ever have. The task for Biden come January would be to maintain a healthy partnership with his vice president—without worrying that she’ll outshine him.

“History tells us that consequential presidents and vice presidents come out at times where they’re tested and tried, and I can’t imagine a period of time where the president and vice president are going to be tested more than in January 2021,” Michael Feldman, a senior adviser to former Vice President Al Gore, told me. “There’s just no chance that the person who he picks is not a consequential vice president or consequential historical figure. They just will be.”