A unionized job once meant a secure path to a middle-class life. Labor unions are still big political players, but they have seen a steady decline in membership and clout since their heyday in the 1950s.
Where they stand:
President Barack Obama has signed a series of executive orders that encourage the use of union labor in federal construction projects, ease union financial reporting requirements and more. He has also appointed labor-friendly members to the National Labor Relations Board, which has approved new rules to help union organizers and has more strictly enforced laws against anti-union misconduct.
Republican Mitt Romney says he will reverse all of Obama's executive orders that help unions, seek to prohibit unions from using automatic dues deductions for politics and strive for national right-to-work legislation that prohibits unions from collecting dues from nonmembers.
Why it matters:
Unions long have been viewed as a way for workers to gain job protections, boost wages and achieve benefits. Many business leaders see unions as limiting employer flexibility and sapping profits.
About 14.8 million Americans are members of labor unions. The number has been declining for decades as domestic manufacturing jobs go overseas and businesses take a tougher approach in opposing union organizers.
Organized labor now makes up just 11.8 percent of the work force -- down from about a third of all workers in the 1950s. Union leaders have looked to the White House and Congress for help in organizing new members and increasing their influence in the workplace.
But favorable union organizing rules approved by Obama's appointees at the National Labor Relations Board have been tied up in the courts. And an effort to get Congress to pass card-check legislation, which would let unions organize new members simply by signing cards instead of holding elections, went nowhere during Obama's first term.
Obama didn't do much to push the card-check law, which faced vigorous business opposition, but he did please unions with his federal bailout of the auto industry and passage of a huge stimulus package -- both credited with saving thousands of union jobs. Romney opposed both moves.
Last year, the labor board's general counsel outraged business groups when he filed a lawsuit against Boeing Co., saying the company was punishing union members in Washington state by opening a new plant in right-to-work South Carolina. While both sides ultimately settled the dispute, Romney says he wants to amend labor laws to prevent the board from interfering with business investment decisions.
In the public sector, where unions had seen some of their steadiest growth in recent years, Republican governors in states such as Wisconsin and Ohio have pushed laws seeking to curb collective bargaining rights for state workers. They argue that such limits are necessary to roll back generous pension and benefit packages that cash-strapped governments no longer can afford.
Romney has praised efforts to limit collective bargaining rights for public workers, while Obama has denounced them. In fact, the Obama administration for the first time granted limited union rights to more than 40,000 federal workers who screen passengers at the nation's airports.
Despite massive public protests against measures limiting union rights and some court successes by organized labor, polls find unions less popular than in past decades. They were viewed favorably by 52 percent of Gallup respondents in August.
Even Democratic leaders in New York, California and other states have sought to limit pensions for state employees and make union members contribute a greater share of health benefits.
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