Transcript for Bernie Sanders Secures Largest Lead Yet in New Hampshire

New signs of trouble for the Hillary Clinton campaign. Bernie sanders surging past her in New Hampshire. Closing in on the gap in Iowa. Jon Karl tracking the race from Washington. Good morning, Jon. Reporter: Good morning. Bernie sanders is coming on strong. Hillary Clinton will have a much tougher battle for the nomination than virtually anybody expected. Hillary Clinton is campaigning P. Reporter: Not long ago, Clinton was trouncing sanders in Iowa. Now her lead is down to 11 points. The big question now, what will Joe Biden do? He's not a kptd yet. In that new New Hampshire poll, 20% of democrats are already saying they'd vote for him. If he gets into the race, we'll have a lively debate. Reporter: Hillary Clinton is also struggling against potential republican opponents. In the two new poll, Donald Trump beats her in Iowa and is tied with her in New Hampshire virtually. And Jeb bush easily beats her in both states.

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