NEW YORK (CNNMoney.com) -- WakeupWalmart.com, backed by the United Food and Commercial Workers International Union, has launched a nationwide bus tour to make its case against Wal-Mart's low wages and restrictive employee benefits.

The "2006 Change Wal-Mart, Change America" tour is traveling from New York City westward across 19 states, making 35 stops and culminating in a Labor Day event in Seattle.

"The idea is to build public awareness and put political pressure on the retailer," said Chris Kofinis, communications director for WakeupWalmart.com. "Wal-Mart has to realize [that] its negative impact on our economy and society is not being ignored."

Wal-Mart (up $0.14 to $44.23, Charts) questions the motives behind the campaign. "This is a union funded publicity stunt that's more about politics than anything else," said David Tovar, spokesman for Wal-Mart. Tovar points out Wal-Mart's $23 a month health plans offered to employees and its creation of tens of thousands of jobs a year. "The fact is they're attacking the wrong company."

WakeupWalmart.com is highlighting the stores' impact on the communities in which they're located, the company's use of tax subsidies and the working conditions of other countries that supply the No.1 retailer with many of its products.

The tour's stops are to include townhall and community meetings, state fairs, sporting events and public squares that the group will canvas to sign up new members.

The first stop was at a community meeting held in a Bronx, New York church on Tuesday. The organizers of the tour hope to sign up 25,000 new members nationwide.

The United Food and Commercial Workers International Union is a part of Change to Win, a coalition of unions that broke off from the AFL-CIO, in the summer of 2005 over differences about union growth and funding priorities. The AFL-CIO also has efforts against Wal-Mart's labor practices underway.

The Change to Win coalition includes the Service Employees International Union (healthcare workers and service staff), United Farm Workers of America, UNITE HERE (hotel workers and service workers), International Brotherhood of Teamsters, United Brotherhood of Carpenters and Joiners of America, and Laborers' International Union of North America.

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