The Last Word with Lawrence O'Donnell 06/30/15

Will Elizabeth Warren campaign for Sanders?

Progressive leader Sen. Elizabeth Warren said it's "too early" to say if she'll campaign for Bernie Sanders. Will she endorse him or Hillary Clinton? When will she pick her candidate? David Axelrod, David Corn, Kasie Hunt, and Thom Hartmann join the show. ... more Duration: {{video.duration.momentjs}}