Current law prohibits municipalities from enacting local living wage ordinances, but exempts ordinances like Madison's, which pertains only to employees of the city, employees working under a contract with the city or an employee performing work funded by financial assistance from the city.

The substitute amendment would preempt such an ordinance in the case of a project funded, in whole or in part, by state or federal funds that pass through the state treasury.

It's unclear as of Tuesday evening what percentage of city projects are funded in this way and what repercussions the substitute amendment will have on Madison.

As of January, employees covered under Madison's living wage ordinance earn at least $12.45 an hour, up from $12.19 in 2013. The city's living wage is adjusted annually and is equal to 110 percent of the federal poverty line.

The bill is being introduced less than a week after the Milwaukee County Board approved its own living wage ordinance. The ordinance has not yet taken effect and Milwaukee County Executive Chris Abele may veto it.