When I go to hell, @surveyusa is going to be there telling me it's 67 degrees.— Paul Mitchell (@paulmitche11) November 1, 2016
The Field poll is the gold standard. They nailed the Brown-Kashkari result in 2014. Right now Donald Trump is polling at a slightly closer margin nationally than Mitt Romney did. Because California is roughly 10% of all votes, it closely correlates with the national changes. If Hillary Clinton were to win by the 36 points Sacramento State had in their poll, she isn't going to win nationally by a smaller margin than Barack Obama. He won by 23 points here.
Field has Clinton with a 20 point lead. They put the already voted margin at 23% and have Trump doing better with later VBM and election day ballots. This is a reverse of past California voting patterns, as Republicans tended to do better in early voting. It’s more in line with Democrats voting heavier early nationwide.
If Field is right, then Trump is likely to do better in individual districts than Romney did in 2012. Trump is likely to win districts Romney won and maybe one or two he didn't. That runs contrary to the media meme that Trump would get slaughtered in California, especially in swing districts. It's likely that Trump will improve on Romney a bit more in Whiter districts and may lose some ground in heavier minority districts but if Clinton wins the state by a similar margin as Barack Obama did, voting patterns should be similar to 2012. Democrats have been trying to tie Donald Trump to swing district Republicans. If Trump has similar results to Romney, that won't work.