We don’t nominate candidates or elect presidents on a national basis, so why do they even waste their time doing these national polls?
To manipulate the outcome, to get the result they want.
At the moment, so they (meaning the MSM) can concentrate on giving Obama a boost and only report allegedly 'national' numbers so they don't have to report on the upcoming Pennsylvania primary where it looks as if Hillary may kick their boy's ass. I'm hoping she does so that this most entertaining of races is extended as long as possible. A race that will drain both candidates resources to the max.
IOW, 'they' are trying to influence an election. Nothing new.