If you’re taking a look at the last election, you’ll see that Hillary Clinton won massively in California’s big cities by a significant margin, but also in New York, Washington DC, Detroit, basically in most of America’s massively populated metropolitan areas.
One may argue that big cities are harboring America’s progressive elite and the so called elite, even if it makes no sense, tends to vote left, i.e. for more state and more welfare (socialism basically), which is the Nemesis of (genuinely hatred by many intellectual idiots) capitalism, the economic system that made America and the rest of the civilized world great.
However, to understand Democrats/Hillary winning the metropolitan areas one must look deeper than that.
All across the United States there are over three hundred governmental jurisdictions which are currently claiming sanctuary status. Of those areas, 106 are cities while the rest of ~200 are counties, states or other units of government.
President Trump’s administration is looking into improving America’s migration system, especially by cracking down on illegal (undocumented) aliens. According to official reports, there are over 11 million illegal immigrants in the US, of which more than half take shelter in sanctuary cities like San Francisco, i.e. in big metropolitan areas.
All the aforementioned data was collected by the Pew Research Center and Statista and it’s worth mentioning that some of these metro areas feature sanctuary cities at their center. Basically, twenty metropolitan areas are home to 60% of the illegal aliens in the United States.
The largest populations of illegal aliens are to be found in Los Angeles, New York and Houston, which coincidentally voted in mass with Hillary Clinton who promised amnesty in her first 100 days, as opposed to the anti-illegal immigration candidate Donald Trump who won the rest of the “flyover America”.
The US illegal immigrants are highly concentrated in just a few large cities as per the picture below:
I will close with an older article from Huffington Post which is a heavily left-leaning/anti Trump media outlet and I’ll let you to draw the conclusions: Democrats Benefit From Illegal Immigrant Voting