The Occupy Wall Street movement could offer a similar opportunity to left-wing politicians as the Tea Party movement did to the right, says a Vanderbilt University historian.

Occupy Wall Street is a continuing series of demonstrations in New York City that has spread to more than 70 other cities. Participants have said they are protesting corporate greed, the influence of lobbyists on lawmakers and general social and economic inequities in the United States.

“We don’t know yet whether Occupy Wall Street along with the worsening economic crisis will gel into a powerful mandate like the labor movement that took root four years after the Great Depression began in 1929,” said Gary Gerstle, the James G. Stahlman Professor of American History at Vanderbilt. “But history teaches us that movements that begin in very fragmented, unexpected and surprising ways can go on to wield a lot of influence.”...