According an The Hill article here are the top 10 cities with highest murder rate:
- Jackson, Mississippi
- Birmingham, Alabama
- St Louis, Missouri
- Memphis, Tennessee
- Baltimore, Maryland
- Detroit, Michigan
- Cleveland, Ohio
- Louisville, Kentucky
- Indianapolis, Indiana
- Oakland, California
I can't imagine any of them having a Republican mayor, but I don't hold mayors responsible for actions of their citizens.
Perhaps more to the point is questioning what political party do the CEOs of gun manufacturers belong to? I never cared enough to look that up either.