IT'S BEING CALLED "Workers Stand for America" — 30,000 union members packed in front of the Philadelphia Museum of Art on Saturday morning to say that any loss of power by organized labor is a danger to the middle class.

It could just as well be called "Mixed Messages for the Masses," as unions scramble to find the right tone to attract attention.

Local union officials paint Republicans as anti-worker while lamenting being taking for granted by Democrats. The officials deny that the rally is a "shadow convention," while griping about the Democratic National Convention being held in anti-union Charlotte, N.C., in early September.

They want to flex their political muscle to send a message. But is anyone listening?

Union leaders gathered Monday at the headquarters for Local 98 of the International Brotherhood of Electrical Workers to voice their frustrations.

There were a few salvos fired at the GOP. Pat Gillespie, business manager for the Philadelphia Building and Construction Trades Council, complained about "tea baggers and Republican manipulators" casting unions in a bad light.

But most of the concerns were expressed about Democratic allies. John Dougherty, Local 98's business manager, said that labor has been in a "complacency coma."

"I want to thank the [Democratic National Committee] for waking us up," Dougherty said. "The days of taking the labor movement for granted are over."

President Obama will not attend Saturday's rally, and it was unclear Monday if anyone from his campaign would play a role.

Jamie Horwitz, a spokesman for organizers in Washington, said that U.S. Rep. Debbie Wasserman Schultz, chairwoman of the Democratic National Committee, and AFL-CIO president Richard Trumka are scheduled to address the rally.

Larry Sabato, a political scientist at the University of Virginia, predicts that the rally will have little mpact on the 2012 presidential election. Union members who voted for Obama in 2008 won't support presumptive Republican nominee Mitt Romney or will skip voting this year, he said.

"There's always grumbling," Sabato said. "That's in the nature of interest groups. They always want more attention."

University of Illinois professor Bob Bruno, who studies labor and employment relations, said the unions are trying to walk a fine line with a goal of remaining allies with the Democrats, while still advocating for a pro-labor agenda.

"Historically the Democratic Party has been a much friendlier party to organized labor," Bruno said. "But the paradox is, because there is no other good choice, they find themselves having to support a party that — certainly since the Bill Clinton era — is less robust for organized labor."

Bruno said that a sign of success will be if Obama or Vice President Joe Biden echo at the convention any of the language spoken at Saturday's rally.