CA was an ideal state for Ds in 2016. First, it has Mexicans and Trump is the opponent - enuf said. Second, its a suburban state - its cities aren't too urban and its rural areas aren't too rural (leaving out the desert where nobody lives). Hillary's campaign was all about suburban voters, while Obama was more about urban turnout. And finally, its economically depressed areas (Trump's base) are relatively few.
If anything I'm shocked how Hillary did only 1 point better than Obama 2012 and the same as Obama 2008. Its probably some combination of maxing out the D vote and Hillary being a terrible candidate.
third parties bruh