Graduate students at many public universities already belong to unions.
More than half of the company's employees belong to national unions.
Many of these employees belong to unions who say how much their members must be paid.
Most of the city's direct employees also belong to unions.
Union membership has fallen by more than 3 million since 1980, and just 16 percent of American workers belong to unions.
People here belong to unions and vote, usually for Democrats.
About 20 percent of Spain's 10 million workers belong to unions.
Across the nation, 16 percent of workers belong to unions, which is about half what the rate was during the 1950's.
Most of those workers belong to unions that have often supported Democratic candidates.
How relevant is the labor movement to the 86.5 percent of Americans who do not belong to unions?
