It doesn't make a bit of difference, NYC is behind him, so he will be re-elected.
If I ever ran for Governor... and if I had access to resources to run a statewide campaign I absolutely would consider it... I would run a "divide and conquer" campaign of sorts.
I already know that New York City is far more liberal on the whole than I am. So instead of trying to impose my philosophy on them, I would give them more power to run their own affairs, in exchange for letting the rest of the state have authority over their own. If Bill de Blasio and company want to make New York City a progressive capital, who am I to stop them?