The Last Word with Lawrence O'Donnell 12/14/15

New polls: It’s Trump v. Cruz

Ted Cruz is beating Donald Trump in new polling in Iowa. So now Trump is attacking Cruz. Plus, Bob Saget gives the comedian's take on Donald Trump's presidential campaign. NBC’s Hallie Jackson and Jonathan Alter also join MSNBC’s Lawrence O’Donnell. ... more Duration: {{video.duration.momentjs}}