The future of a massive $30 million effort by organized labor to turn Republicans out of Congress and the White House has been cast into doubt after a top union leader cut his ties with the organization running the program.

Union insiders said hostility toward the project’s director, Steve Rosenthal, among key labor constituencies culminated in the decision by Gerald McEntee, president of the American Federation of State, County and Municipal Employees, to resign from the group.

The Partnership for America’s Families, a tax-exempt 527 group created this year to collect the millions of dollars in soft-money contributions unions used to give to the Democratic Party but which are now banned under last year’s campaign finance law.

McEntee announced his departure from the group, along with that of the AFL-CIO’s Linda Chavez-Thompson and former New York Comptroller and Democratic gubernatorial nominee Carl McCall, in what labor insiders described as a scathing letter to Rosenthal, first reported by ABC News.

Some labor insiders suggested that underlying the move is an intense battle still raging between Rosenthal and minority coalitions within the labor movement over actions he took during his seven-year tenure as political director at the AFL-CIO.

“There’s been a lot of turmoil since the thing started,” said Oscar Sanchez, the leader of the Labor Council for Latino American Advancement, one of the groups that has spearheaded opposition to Rosenthal.

“How could labor support someone who had been such an obstacle, such a detriment to minorities and women in the labor movement?” asked Sanchez.

In an interview Friday, Rosenthal vehemently defended his record of outreach to minority groups, and other labor officials privately said the dispute with McEntee was more about “ego and personalities” within the upper ranks of the labor movement than a battle over registering more minority voters. McEntee and Andrew Stern, president of the Service Employees International Union and a key Rosenthal ally, are bitter rivals, and the two have taken opposing sides in this latest fracas, said the sources.

Rosenthal said his organization had encountered merely a “speed bump” with the high-profile departures by McEntee and the other board members, and vowed that he would “reconstitute” the board as early as this week.

Rosenthal also denied suggestions that the decision by AFSCME to withdraw from his group will prevent it from reaching its financial and political goals this cycle.

“As with any new organization there are going to be some growing pains,” Rosenthal said in an interview Friday. “We’re in the process of putting together something that’s never been done before.”

In addition, Rosenthal dismissed charges that he had been insensitive to concerns of minority groups while serving as the AFL-CIO’s political director.

“I’ve spent a lifetime working on civil rights issues within the labor movement and outside the labor movement,” said Rosenthal.

“Nobody did more to increase the AFL-CIO’s participation in and relationship with the [Congressional Black Caucus], the [Congressional Hispanic Caucus] … and black and Latino officials around the country than me.”

The Partnership for America’s Families has been expected to serve as a base for liberal groups hoping to coordinate turnout efforts for Democrats in the 2004 election, and has banked about $1.5 million so far.

But the project stirred controversy within labor circles from the moment Rosenthal was named its director, and major unions like the Teamsters have declined to join.

Despite the fact that his own union had committed to providing Rosenthal with as much as $2 million in funding, William Lucy, AFSCME’s secretary-treasurer and leader of the Coalition of Black Trade Unionists, angrily denounced Rosenthal at labor’s executive council meeting in February, according to several participants.

The sources described Lucy as being somewhat incredulous that Rosenthal, who had clashed continually with the minority coalitions during his tenure at the AFL-CIO, would be heading up the effort to organize black and Hispanic voters at the grass roots. One source remembers Lucy saying, “I know a thing or two about being black,” during an angry tirade directed at Rosenthal personally.

“You know when it gets to that after [Rosenthal has spoken only] one sentence, there’s a problem,” the source said.

Lucy, who was attending a meeting of the black labor group in San Francisco late last week, did not return calls seeking comment.

Some leaders in labor’s minority coalitions contend that Rosenthal consistently and actively undercut their interests at the AFL-CIO and never adequately supplied the resources they needed to be effective.

Citing that history, Sanchez derided Rosenthal’s selection to lead the get-out-the-vote effort as “plantation politics,” and said it had evolved into an “emotional” and “passionate” issue for labor’s minority coalitions.

“How could we stand by, knowing what Mr. Rosenthal had done?” Sanchez asked. “The minority groups felt it was ironic that a guy who had never lent a hand to minorities was now going to be leading the effort to register people in our communities.”

But several union officials claimed Sanchez and Lucy were really angry that Rosenthal had declined to pump as much money as they wanted into their organizations while he was at the AFL-CIO.

“It was about performance, and those groups did not do as well as Steve wanted them to,” said a pro-Rosenthal labor official.