it's not that the polls are meaningless due to bad methodology or whatever other thing. i'm flatly suspicious that the polling companies are corrupt. and, i've made this argument in this space already.
i'll just point out that:
1) hillary clinton has not won an open primary since mar 15th.
2) the polling leading up to several of her losses since then favoured her, and was shown to be "wrong".
3) in fact, the demographics also favoured her in several of the states that she lost.
i'd argue that you want to look more at recent contests for predictors. california should fall somewhere between the closed primary in oregon and the open caucus in washington. and, the best guess we've got for jersey is rhode island.