With former vice president Joe Biden’s surprising sweep in the Super Tuesday primaries—he won at least 10 states out of 14 races—would it be smart for him to pick his running mate now? And if he decides to do so—wouldn’t selecting a woman as his future vice president bolster his potential ticket, and the Democrats’ chance for beating Trump in November?

Traditionally, candidates have announced their running mates at their conventions or shortly before. Hillary Clinton gave the nod to Tim Kaine just days before the Democratic convention began in 2016; Obama picked Biden only a few days before the 2008 convention. It may be unusual for a candidate to declare a running mate so early, but could this move perhaps make his candidacy even more competitive—or at least more interesting? After all, there are still important challenges facing the candidate in the coming weeks—next Tuesday will see primaries in Washington, Idaho, Michigan, Mississippi, North Dakota, and Missouri.

Declaring your running mate early has not always brought particular good fortune, however. In 1976, when Ronald Reagan ran unsuccessfully against Gerald Ford, he announced that his VP would be Richard Schweiker, a liberal senator from Pennsylvania; in 2016, Ted Cruz picked Carly Fiorina as his second-in-command. Neither Reagan nor Cruz got the nomination.

Still, if Biden is looking for a bold move, this could be it. Here are six women he might consider.

Amy Klobuchar