There isn’t a massive number of far-left libs in this country, but NYC is a gathering point for them.
If you are watching this story on the news, look at the people milling around in the background and giving interviews - they are the voters of NYC. One guy just said he sympathizes with the families of the cops, BUT he also sympathizes with the families of Eric Garner and Michael Brown. Too many NYC voters see these as similar cases (the two perps and the two cops); DeBlasio won in a landslide, and he’d win in a slightly smaller one if an election was held tomorrow.
I think you underestimate the trouble a mayor who has lost the confidence of his police force is in. That's almost insurmountable in any city anywhere in the country.