if it is john kassig, that means that things will start to shift a little bit. >> reporter: new hampshire could narrow the republican field by four or five candidates. will ben carson, chris christie, carli fiorina, jeb bush and others keep battling on if they fair poorly here? political analyst ed tour andcy sky bush will probably stay to the end but probably not the others. >> christie had a very narrow path to the nomination, new hampshire was critical there. if he doesn't the place second or close third, it may be over for him as well. >> reporter: on the democratic side, new hampshire revived mrs. clinton's campaign in 2008 after president obama beat her in iowa she's hoping to repeat history. bernie sanders is doing his best to put a monkey wrench in there. >> bernie sanders i'm very confident will win new hampshire. he is polling very well. how well he does in terms of the margin of victory is, he is really, really viable. if he wins, new hampshire, i think the democratic primary race continues for some time. the democrats used proportion al-zawahiri case of delegates, so, he could