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The White House’s allies shrug off such complaints, saying Mr. Obama is merely making good on his campaign promises.

“The only way industry should be surprised by this is that they haven’t paid attention for the last 18 months,” said Daniel J. Weiss, director of climate strategy at the Center for American Progress, a liberal Washington think tank.

Sen. Barbara Boxer, California Democrat and chairman of the Environment and Public Works Committee, heralded the president for presenting “a clear path toward passage of a strong global-warming bill.”

“With the latest science on global warming pointing to the need for urgent action, this breakthrough comes not a moment too soon,” Mrs. Boxer said. “This budget makes it clear that President Obama fully intends to keep his promise to prevent the ravages of global warming while investing in clean energy that will lead to a brighter economic future.”

Still, 15 Senate Democrats have signed on to a letter stating principles for cap-and-trade legislation that would “ensure that consumers and workers in all regions of the U.S. are protected from undue hardship.”

The signatories include Mr. Brown, Mr. Rockefeller, Sens. Debbie Stabenow and Carl Levin of Michigan, Blanche Lincoln and Mark Pryor of Arkansas, Jim Webb of Virginia, Evan Bayh of Indiana, Claire McCaskill of Missouri and Ben Nelson of Nebraska.

They have been joined by Democratic Sens. Jeff Bingaman of New Mexico, Robert C. Byrd of West Virginia, Kent Conrad and Byron L. Dorgan of North Dakota, and Tim Johnson of South Dakota.

The tenets, outlined in a June 2008 letter to Mrs. Boxer and Senate Majority Leader Harry Reid of Nevada, include demands for cost controls and prevention of economic hardship; equitable treatment of affected states; price relief for families facing higher energy bills; and protections for U.S. manufacturing jobs.

“Senator Webb believes that the U.S. must work in concert with the world community to achieve meaningful, long-term reductions in carbon dioxide emissions,” said his spokeswoman, Jessica Smith. “As proposals are being debated in the Senate, he believes that scientific principles should be applied in a way that both preserves our environment and allows for sensible economic growth.”

Satisfying both environmental and economic priorities with a cap-and-trade law is a daunting task. The White House hopes to gain leverage by using the new revenue to pay for Mr. Obama’s signature “Making Work Pay” middle-class tax breaks.

“Cap-and-trade system will have some effects on households,” White House budget director Peter R. Orszag said last week. “That’s one reason we are linking the cap-and-trade program to making work pay.”