Disputing Bush administration estimates, a liberal think tank said yesterday that new federal rules will remove overtime protections for at least 6 million U.S. workers.

The study by the Economic Policy Institute was released a day after three former Labor Department officials said in a report that large numbers of employees entitled to overtime would no longer be so protected when the new rules take effect Aug. 23.

The report by the former Labor officials, which was requested by the AFL-CIO, said the change was likely to be significant because "more classes of workers and a greater proportion of the work force overall will be exempt than we believe the Congress could have originally intended."

The EPI report estimated that nearly 2 million administrative workers who can be classified as team leaders would lose overtime protection. An additional 920,000 workers who can be reclassified as learned professionals, even though they do not have college degrees, would be similarly affected. It also said 1.4 million workers could lose overtime protection by being reclassified as executives, as could an estimated 130,000 chefs and cooks, 160,000 financial service workers and 117,000 teachers and computer programmers.

The Bush administration took issue with the findings. "These latest studies are a rehash of misinformation that the AFL-CIO put out about the department's final overtime security rule in April, assertions that were completely discredited in congressional hearings," said Labor Department spokesman Ed Frank.

The department estimates that as many as 107,000 workers making $100,000 or more annually could lose overtime under the new rules, while 1.3 million low-wage workers who are denied overtime will become eligible.

On a party line vote yesterday, the House Appropriations Committee rejected an amendment by Rep. David R. Obey (D-Wis.) that would have prohibited any reduction in the number of workers eligible for overtime.

Sen. John F. Kerry (D-Mass.) has said that if elected president, he would move immediately to restore overtime protection to those who would lose it. The presumptive Democratic nominee said the analysis by the former Labor officials, who worked in Republican and Democratic administrations, demonstrated that the Bush administration rules "represent a shameful assault on the paychecks of hardworking Americans."

The EPI said its estimate that 6 million workers will be denied overtime is based on revisions to the regulations issued in April. The original proposal from the administration would have eliminated overtime protection for 8 million workers, the EPI report said.

Democrats in Congress said the new reports supported their assertion that the administration was distorting the effect of the new regulations.

"The administration's public posture is smiles and happy talk, including the audacious claim that no worker earning less than $100,000 will lose their right to overtime," said Sen. Tom Harkin (D-Iowa), who is leading the fight in the Senate to block implementation of the new rules.