Polls? What polls?

A Voice of America piece on the future of unions, reports this about younger workers:

"Another potential avenue for union growth is organizing America's younger workers. Public opinion surveys indicate that young people, who hold many service-sector jobs, tend to be more supportive of unions than those in their parents' generation. But Cornell University's Richard Hurd cautions that it will be difficult to turn that support into union membership."

Dying to know what polls, though...