caucuses colliding with martin luther king holiday tomorrow. and about what his party needs to do, to not just unify against the eventual republican nominee, but to bring disaffected democrats, black voters specifically, back into the fold, ahead of november. let's check on the latest from iowa, however, with nbc's priscilla thompson in sioux city. priscilla, please start with the weather, any concern that it will affect the voting tomorrow? >> yeah reverend al, there is certainly concern that this could dampen turnout, especially among the campaigns. it is why you have seen the candidates out on the trail over the past several, days urging their supporters to get out and caucus, to brave that wetter. and let me tell you what type of weather we are talking about here. we are talking about sub zero