By Brendan O'Brien
MADISON, Wis., March 5 (Reuters) - Wisconsin lawmakers on Thursday will begin a final debate on a measure supported by Republican Governor Scott Walker that would prohibit private-sector workers from being required to join a union or pay dues when working under union contracts.
Walker, a presidential hopeful, is expected to sign the so-called right-to-work bill next week if it gets to his desk after what could be a 24-hour debate in the state Assembly starting on Thursday morning.
The state Senate approved the bill last week, and the Assembly, where Republicans hold a 63-36 majority, is expected to follow suit to make Wisconsin the 25th state to enact a right-to-work law.
Supporters cast the measure as an incentive for keeping and attracting businesses and jobs, while opponents call it a thinly disguised assault on organized labor.
Thousands of workers demonstrated last week when senators debated the bill, but capitol crowds have been far thinner than four years ago, when tens of thousands of people protested a push for a law limiting the powers of public sector unions.
Walker's push for the bill covering public-sector workers raised his profile among Republicans, and his support grew when he survived a union-backed recall election in 2012. He has emerged as an early favorite in the battle for the Republican nomination in the November 2016 presidential election.
This year's bill would bar private-sector workers from being required to join or financially support a union, such as by paying dues, as a condition of their employment.
"A law like this would have never been entertained two decades ago," University of Wisconsin-Madison political scientist John Ahlquist said. "The law is a symbol of the weakness of unions."
About 8 percent of private-sector workers in Wisconsin are union members, down from about 22 percent three decades ago, according to Unionstats.com, a website that tracks U.S. union membership and labor statistics.
Ahlquist said the law may make it harder for organized labor in Wisconsin to create new unions and, over time, it could reduce union membership as workers retire or move out of state.
The pressure on union membership in turn weakens Democrats, who are typically backed by organized labor, Harvard Law School labor expert Benjamin Sachs said.
"This law disables the political opposition," Sachs said. (Reporting by Brendan O'Brien; Editing by Mohammad Zargham)