U.S.   –  As Hillary Clinton returns to Iowa on Monday, a sense of anxiety is cascading through her campaign, with an increasing sense of urgency the primary fight with Bernie Sanders is far more of a threat than once imagined, unlikely to be extinguished after the first contests in Iowa and New Hampshire.

Clinton has gone from all but ignoring Sanders to fiercely engaging him in recent days, a reflection of public and private polling that points to a race that is uncomfortably competitive for the Democratic front-runner. She openly questions his electability and argues that he is out of step with the party on guns and other issues. (CNN.COM/photo:Wikimedia.org)…[+]