At least where I am from "Working Class" implies skilled labor like Electrician or Carpenter, and some white-collar jobs like realty agents, nurses and teachers. People who make $35k-$60k.
People making $20k, like landscapers, janitors, forklift operators, and loaders, are generally called "Unskilled Laborers", not working class.
People making $20k, like landscapers, janitors, forklift operators, and loaders, are generally called "Unskilled Laborers", not working class.