Emily Badger sums up research looking at how much big cities are affected by having a mayor from a particular political party:

Numerous studies suggest that the partisanship of mayors has limited effect on much of anything: not just crime, but also tax policy, social policy and economic outcomes.

The researchers Justin de Benedictis-Kessner and Christopher Warshaw have found that Democratic mayors spend more than Republican mayors. “But the differences are pretty small,” said Mr. Warshaw, a political scientist at George Washington University. “They’re not enough to drive large differences in societal outcomes in things like crime rates.”

This is partly because mayors are constrained in their ability to execute ideological agendas. Cities can’t run deficits. States limit their authority to raise taxes and enact laws on many issues. And cities lack the power the federal government has to shape labor laws, or immigration policies that can affect their population growth…

Cities have been faced with problems far beyond their making. Deindustrialization and globalization wiped out many middle-class factory jobs, destabilizing neighborhoods of blue-collar workers. The federal policy of highway construction enabled both taxpayers and employers to leave cities. Federal housing policies dissuaded or prevented Black residents initially from joining them, cementing patterns of racial and economic segregation that persist to this day…

There are plenty of fair critiques of decisions that Democratic mayors do control — regarding charter schools, or how equitably they deploy city resources, or whether their zoning laws and school policies perpetuate segregation. And there is room to criticize the Democratic Party’s failure to devise a coherent federal urban policy.

Disentangling this from the current political moment and debate about running cities, a few themes from the article stuck out to me:

1. One argument is that mayors are more interested in pragmatic day to day city processes than larger ideological concerns. Mayors themselves make this argument. If a mayor cannot help solve a particular local problem, they may not be in office for long, regardless of what party they align with.
2. Cities are stuck between multiple bodies of government. A city may be nested within a county (and this is what might make city-county mergers appealing), a state, and then the federal system. On one hand, cities are essential to our modern society – they are economic engines, centers of culture, gathering places for residents and jobs, anchors of entire regions, etc. – but their city interests must be negotiated with other bodies of government above them. Putting it in more sociological terms, cities are between macro and micro social scales yet often are viewed as macro entities and have some capabilities at the macro level (I am thinking of conferences of mayors, transnational conversations between mayors and other mayors or heads of government, etc.)
3. As a graph in the article shows, there are more Democratic big city mayors than Republican big city mayors and this has been true for decades. Do Republicans want to be mayors of big cities? Also noted in the story: Republican policies and appeals have been made to suburbanites and rural voters for decades, less so to urban residents.
4. This is not a new political issue; the United States has a long-standing divide regarding cities that goes back to the founding of the country. For more on this as it played out in the twentieth century, I recommend the 2014 book Americans Against the City by historian Steven Conn.