The frontrunner there for months,onald trump has fallen behind to ben cacaon. Well speak with dr. Carson live in a moment. But first, the shrinking field of Democratic Candidates gathered last night in iowa for a big dinner thats o ten been a turning point. Chief white house cooespondent ed henry is live in des moines to tell us what happened. Ed . Chris, for Hillary Clinton, this was a political equivalent of a defens shes back in the leadadid not want t t make a mistake. She played it so safe, it opened the door for bernie sanders, the democratic socialist senator to electrify this crowd of over 6,000iowa democrats. She brought along her husband bill for his first rally of this campaign cycle, plus pop star katy perry. The comeback kid declaring that after what was obviously a brutal start to hercampaign, his wife has had a remarkable few weeks from a strong debate performance to a series of democrats simply dropping outf this race. So the front runner used this big democratitidinner