We know Joe's VP will be a women, but how to balance the ticket? On what principle?

[andym]

The ticket is typically balanced on geography. However, in reality the ticket should always be balanced on helping to gain voter blocks that the candidate doesn't attract as well.

So which voting blocks did Biden have a weakness with during the primary?
African Americans? NO. Women? NO Latinos (Somewhat), Younger voters (less than 45) (Yes).

Basically those younger than 45 according to the well documented "age gap" in the primary. Joe's running mate should be someone who can increase turnout and enthusiasm among younger voters--maybe not the teens to 20'a crowd, but those 30-45 who vote more reliably than the 18-29 demographic.

In these troubled times, there is another key qualification, Joe has to pick someone who is viewed as experienced and competent enough to take charge in an emergency.