Just general thoughts on all of the candidates
-Donald Trump needs to prove he's not just a media boy and is a serious contender for the United States' Presidency. He's leading most recent polls in New Hampshire but unusually high numbers. And New Hampshire loves to play contrarian so maybe it'll help him cement his front runner status. He wasn't really expected to "win" Iowa until extremely recently.
-Marco Rubio needs to win a state. It's amazing he came in third, but third place in every state just wont cut it. You gotta win. He has a lot of momentum for sure and the establishment loves that but consistently losing will drain him of his funds/candidacy quickly. He can survive 6-8 losses in a row, but after that things get dicey
-Ted Cruz needs to now show he's in it to win it. He was expected to win Iowa because he's been up all along and the evangelical vote pushed him over the edge. He solidified his candidacy with an Iowa win but can he win outside of that demographic?
-Ben Carson needs to get serious. I don't think he has a legitimate shot anymore but if he wants to win the nomination he needs one of the next few states. Any place under 3rd and he'll drop out before mid March
-Carly Fiorina, Jeb Bush, Rand Paul, Chris Christie, and John Kasich need to prove to the establishment that Rubio is bad news. He has questionable immigration views they need to hammer him for but they haven't done that

. Jeb especially needs to turn his attack ads, money, and notoriety into results. 4 of these 5 drop out before the next 4 states.
-Hillary Clinton did well with Iowa but I'm not sure if she can breathe easily as she claims. All year long last year she has lead Bernie Sanders by 40+ points nationally and over 20 points in Iowa. She literally just beat him by 0.4 points. If she can endure a New Hampshire loss and the media's extensive coverage of a "political revolution" and stamp her front runner claim in South Carolina she'll be on track. Look out for Nevada. While she leads among non-whites by over 40 points, caucuses seem to favour insurgent candidates
-Bernie Sanders took a big loss and turned it into a big win. He'll easily generate many donations from Iowa and he's proven he is here to stay in terms of campaign viability. But the thing is, he couldn't handily put away Clinton in an extremely white, liberal state like Iowa, the same demographics as New Hampshire. If he's not easily winning his "friendly" states how can he make a play for the moderates/non whites that'll come in almost every state following New Hampshire? He needs to keep his 30+ point lead over Clinton in NH and cut into her 40+ point lead to have a serious shot at upsetting her a la 2008. It all starts with Nevada, after NH. If he keeps it close/wins there, expect a 2008 rematch. If he loses both states, this nomination will be wrapped up long before June even if he plans to stay in the race until then.
