Part of the Washington Examiner's weeklong commentary series on labor unions. To see the entire series, click here.

For decades, “union man” meant hard hats, lunch pails and blue-collar jobs for millions of American autoworkers, machinists and coal miners.

A union job meant good pay and benefits, but it also promised lots of hard work and, in many cases, a real possibility of being injured.

Back in the 1950s, when U.S. manufacturing dominated the world, one of every three American workers carried a union card.

Unions were taken for granted as a part of American life. Their leaders could even be bipartisan when the occasion required working with political leaders on both sides of the aisle.

Not today. Big Labor represents far fewer workers, and its leaders are closely tied to the Democratic Party. Half of the nation's unionists are white-collar government employees, not private sector workers.

Union membership has been sliding for years, with only 14.5 million people now in a union, or about 11.3 percent of the U.S. workforce, according to the Bureau of Labor Statistics.

Only 6.7 percent of all private sector jobs are unionized, compared with 35.3 percent of the public sector.

Organized labor has lost 3 million members since 1984. As recently as 1980, there were 20 million union members.

Big Labor's future is anything but assured. It faces the very real possibility of dying out, becoming little more than a few chapters in the history books.

But what will the unions of the future look like? As long as people have jobs, there will be a need to address their employment concerns. The question is, how?

Strong indicators show a move away from the rigid, top-down model created under the 1935 Wagner Act -- which assumed unions always represented workers' best interests.

In place of the old model will likely be a new, democratic approach that gives individual workers more options for representation while requiring greater accountability and transparency from their representatives.

Experiments are already under way. Governors in Indiana, Michigan, and Wisconsin have brought variations on right-to-work laws to the Rust Belt, limiting compulsory unionism -- something unthinkable just a decade ago.

Detroit's bankruptcy has created a major precedent for local governments to restructure their union contracts, and make them affordable for taxpayers already stretched by the demands of government spending.

Labor law experts are eagerly watching the Supreme Court's ruling in Harris v. Quinn, due this summer, which could rewrite the rules on public sector unions.

Republican lawmakers in the nation's capital have proposed the Employee Rights Act to reform union elections by guaranteeing secret ballots and requiring periodic recertification votes.

Such reforms would require unions to only represent those who want to belong, forcing them to become more service-oriented.

“We are already heading this way. Unions have to be relevant and provide a service. They cannot automatically assume that people are going to join and be supportive,” Wisconsin Gov. Scott Walker told the Washington Examiner.

Walker said most unions oppose things like merit pay because they erode worker solidarity. Unions also defend poor performers on the job.

“One thing I learned when I worked at the county level that frustrated public sector workers all of the time is that they thought they were carrying the weight for other workers who weren’t living up their responsibility,” Walker said.

Heritage Foundation labor expert James Sherk argues that it makes no sense in a highly fluid, mobile workforce to tie union membership to specific jobs.

“It would make a lot more sense to have a more service-oriented model in which the union dues buy services [for workers] that come irrespective of where you work," Sherk said.

Another possibility would be to allow employer-backed worker representative groups. The National Labor Relations Act doesn’t allow such groups unless workers also have a traditional union.

There are also countervailing trends like the “micro unions” being encouraged by President Obama's appointees on the National Labor Relations Board.

Big Labor has started to experiment with new models that aren’t based on collective bargaining or full representation. But little has come of such efforts.

The case of the Change to Win coalition is telling. In 2005, some of the largest unions bolted from the main labor federation, the AFL-CIO, to create an “innovative” new movement. The effort flopped, and several coalition members have since returned to the AFL-CIO.

Big Labor's main reaction to its decline has been to shower money on Democratic lawmakers who then support pro-union legislation like Card Check, which essentially rigs workplace representation elections in the union's favor.

Some Big Labor leaders have also aligned themselves with liberal activist nonprofit groups, with AFL-CIO President Richard Trumka in particular pushing such alliances and even advocating extending union membership to members of groups such as the Sierra Club and the National Council of La Raza.

“Will it dilute us? Look, here's the way I look at it: What we've been doing the last 30 years hasn't worked real well. We need to do things differently,” Trumka told USA Today last year.

Trumka's approach could remake unions in the Image of such liberal activist nonprofits. Trumka has cited the Occupy Wall Street movement as an inspiration.

But some in the remaining industrial unions worry that Trumka would simply end up giving groups like the Sierra Club effective veto power over the labor agenda.

At its national convention in Los Angeles in September, AFL-CIO delegates rejected Trumka, preferring a watered-down resolution that said: “The AFL-CIO and affiliated unions must continue to innovate and experiment with new forms of membership and representation to achieve the ultimate objective of assisting all workers to bargain collectively through an affiliated union.”

One such “new form” would be labor-oriented nonprofit groups — also called worker centers — that do everything except collective bargaining, at least on their own.

An AFL-CIO preconvention guide stated: “These efforts are viewed by many as a key element of a revitalized and successful labor movement.”

But many worker centers are little more than nonprofit extensions of unions. Our Walmart, which agitates against the retail giant, is an arm of the United Food and Commercial Workers. Fast Food Forward, which does the same thing for restaurant franchises, is a subsidiary of the Service Employees International Union.

Under the federal law, SEIU cannot indefinitely picket Walmart without trying to organize it. But Our Walmart can organize protests day and night.

Will these new models attract members? In an interview, Leslie Tolf of the AFL-CIO’s Working America group said the model for reaching young workers is AARP, the senior citizens' activist group.

The idea is that the labor movement must be independent of the worker’s actual job and instead work as a membership organization.

“Work is a very fragmented industry compared with the 1930s, so we have to have multiple levels of solutions,” Tolf said.

Most of these union-backed reform efforts are ultimately intended to shore up the older system, rather than redefine the movement’s relationships with employees and employers.

“Worker centers still assume that workers need a collective contract,” Sherk noted.

Big Labor has also tried alliances with foreign unions to pressure international corporations. The United Auto Workers was aided in its effort to unionize a Volkswagen plant in Chattanooga, Tenn., by the company's German union, IG Metall.

To preserve “labor peace” with IG Metall, VW agreed to an organizing vote and even aided UAW by holding mandatory companywide meetings with union officials while keeping all others out.

It still didn't work. On Feb. 14, workers rejected collective bargaining even after the UAW claimed a majority of the workers signed support cards.

Following the defeat, the UAW demanded that the NLRB order a revote. The union later backed off, conceding in April it would likely lose a second election.

The Chattanooga defeat was the latest evidence that a growing number of workers just aren’t interested in what Big Labor is selling. And time is running out for them to find a new way to meet workers needs in the 21st century.