Big campaign week for O'Rourke and Yang -- what about Biden?

A crowded field of Democratic 2020 presidential candidates now includes former Texas Rep. Beto O’Rourke, who campaigned in Iowa this week, trying to appeal across party lines. Also in Iowa was entrepreneur Andrew Yang, who just became eligible to participate in Democratic debates. Still, a major question remains unanswered: will popular former Vice President Joe Biden run? Lisa Desjardins reports.