Big Cities are on the wane. Those that can flee, will flee. The remainder will be dregs and limousine liberal parasites.
It's up to the residents of each city to take it back from the insanity of the left. That's what happened in New York City in the early 1990s.
It's up to each city to identify its liberator among its citizens.
Giuliani was able to succeed because he was a city boy - an insider.
Each city has its own distinct history, culture, and values. Things are said without being said or written. Business is conducted with winks and with nods. To walk among residents and earn their trust, a politician needs to understand the mores of the entire city, as well as those of each individual neighborhood or block. Residents are loathe to trust or accept outsiders. That's why they can seem hostile to those on the outside. There is a large amount of tribalism because that's what was required for 1st generation immigrants to survive. That passes down through the generations of long-time residents and of neighborhoods.
Eating pizza with a knife and fork is a tell. I grew up close to the city and I none of relatives and neighbors used a fork and knife to eat pizza. My wife's family, who is more suburban, eat pizza with knives forks. To a city kid, that comes off as pretentious.
The Republican Party has much opportunity to recruit among city residents, but, they need Republicans from the city to canvass for new Republican voters.
There aren't too many residents who want higher taxes and more crime. That crap comes from the limousine liberal pols with liberal agendas or corrupt politicians profiting from the criminals.
Josh Kraft lost the Boston mayoral primary because he was a carpetbagger - he was not a long-time resident of a Boston neighborhood. He resided in a nearby suburb. Kraft wasn't one of them (residents/voters); Wu was.
For the Republican Party to grow in urban areas, it needs to do so precinct by precinct, ward by ward - grow from the bottom up.