Sen. Bernie Sanders' campaign is showing signs of strength heading into Monday's Iowa caucuses – and a source of tension at its heart.
Sanders’ more strident supporters tend to demand that everyone unite behind the Vermont senator if he’s the Democratic nominee but are less forceful in pledging to back the nominee if it’s not him.
Sanders himself is trying to tamp down that divide, insisting Saturday in Iowa that his campaign will support the nominee and that he expects others to do the same. If Sanders achieves unity by compromising on stands he has taken for decades in political office, he could disappoint supporters.
