Just as in 2008, the national polls mean next to nothing. At this time in our Democratic primary process, Obama was far behind in every national poll. In most states, he was behind well into the double digits; in many states Obama was behind Hillary by 40+ points.
And yes, just like 2008--all of these polls are touted by Hillary and her minions, as evidence of her inevitability.
These national polls mean very little because it is the state polls that mean the most.
Since we have individual states vote one-by-one--those state polls mean the most.
Does anyone remember how Obama was polling, at this juncture in 2007? Ten weeks before the Iowa caucus, Obama was 10 points behind Hillary. Today, Sanders is just 15 points behind Hillary.
Despite being 10 points behind, ten weeks out--Obama won the Iowa caucuses by 8 points. In ten weeks, Obama gained 18 points.
Anything can happen in Iowa. Support for Clinton is soft. She came in third last time. She doesn't play very well here with her impersonal, canned campaigning.
If Bernie can kick his campaign into high gear for the remainder of his Iowa campaign, he can win the Iowa caucuses. Even coming in a strong 2nd would be wonderful. He's likely to win NH, as he has been ahead in most polls.
So, don't worry so much about those national polls. They were useless in 2008. Hillary was winning ALL of them at this point and Obama was our nominee. When the campaigns roll into these states, the dynamic quickly changes and voters become engaged. Hillary has the advantage at first, because of name recognition--but in many states that advantage will erode. Especially if Sanders does well in Iowa and wins NH.