Democrats preparing for final debate before Iowa caucuses

Six Democratic presidential contenders are preparing for Tuesday's primary debate in Des Moines, Iowa. It's the final debate before the first nominating contest in early February. CBSN political contributor Molly Hooper joined CBSN AM to preview the debate.

democratic debate,Iowa,iowa caucus,Bernie Sanders,Elizabeth Warren,joe biden,Amy Klobuchar,tom steyer,pete buttigieg,