A controversial measure that proponents say would create jobs but critics say would hurt middle-class families is now on life support, according to the Senate Majority Leader.

Union members by the hundreds filed into the state Capitol on Monday morning as a group of Senate lawmakers discussed a proposed constitutional amendment that would make it harder for unions to organize. Critics of the bill say it would lower wages and cut benefits for middle-class families. Supporters say it would help businesses create new jobs.

Leaders in the AFL-CIO, which produced the ad that starts airing Tuesday, says the bill is "a power grab" meant to weaken collective bargaining. Union members worry it would ultimately lead to less compensation for middle-class families, but Republican legislators behind the bill say it would attract new business and create jobs.

Union members are coming by the busload to protest a constitutional amendment that would end a requirement that some workers belong to unions. Labor leaders say it would only mean fewer jobs and lower pay.

Some Republican legislators are urging leaders in the House and Senate to move the controversial bill through committees and onto the floor for a full vote.

Republicans say the plan would help attract businesses and create jobs, but Democrats say it would boost business profits on the backs of the poor and middle class. Senate Republicans have introduced their own version of the bill, but their plan does not include cuts to renters' refunds.

Graduate students at the University of Minnesota are taking another shot at unionization. This time proponents of the idea have joined up with the United Auto Workers. A vote to organize would mean students would be obligated to pay dues (even non-members), and the school would be obligated to bargain in good faith.