criticizing rivals who refused to call out trump. >> anyone who is unwilling to say that he is unfit to be president of the united states is unfit themselves to be president of the united states. >> reporter: and wolf, one factor we're all keeping an eye on here is the weather in iowa. we've got a major snowstorm that is set to hit iowa in the coming hours. how will that affect candidates events tomorrow and heading into the weekend. caucus day on monday it's expected today be the coldest caucus day ever, the coldest january day in iowa in five years. wind gusts up to negative 40. and wolf, when you're covering presidential politics and elections there can be jokes about it's all about turn out but with those conditions candidates and their campaigns are going to have to make sure their supporters get to those caucus sites. >> the ground game will be critical indeed. jessica dean, thank you very much. joining us now the new hampshire