PPP was the best primary poll for Hillary in months. And yet even they have Sanders with a net favorable rating 21 points better than her, and him doing better in the general election. Now, I know NH isn't the whole country, but people in NH are paying a lot more attention to the election than the country as a whole, so it gives you some idea how the candidates do under increased scrutiny.
Increased scrutiny hasn't yet started. Try again in 2 or 3 months. The only candidates who have received some kind of major scrutiny so far have been Trump and Hillary. Other candidates will follow with time, especially if they happen to rise in the polls.
