Defying a veto threat by the White House, the House of Representatives on Thursday approved a bill to permanently eliminate all authority of the Environmental Protection Agency to regulate greenhouse-gas emissions.

Despite Washington's preoccupation with devising a budget resolution to avert a government shutdown, House Speaker John Boehner brought to a vote a largely symbolic bill aimed at curbing EPA regulatory authority on climate change.

That might seem strange given that the bill – approved 255 to 172, with votes falling mostly along party lines – is not expected to become law.

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A key reason: No fewer than four measures to curb EPA authority, including one with the same wording as the House bill, failed in the Senate Wednesday, falling far short of the 60 votes needed to prevent a filibuster. Moreover, President Obama has said he would veto such a bill.

So why vote at all? For one thing, the House vote puts on record, in time for the 2012 election cycle, which legislators voted for and against curbing EPA authority on climate-change regulations, analysts say. For another, the bill allows Republicans and a handful of Democrats to demonstrate continued determination to rein in the EPA on climate change.

A spokesman for the petrochemical industry hailed the bill as "an important victory." While many jobs have already been lost under existing regulators, the economic impact would be worse "if EPA's greenhouse gas regulations are allowed to continue unchecked," Charles Drevna, president of the National Petrochemical & Refiners Association, said in a statement.

Environmentalists, however, deplored passage of what they call the "Dirty Air Act." “Today House members had a choice: stand up for the health of our children, elderly citizens and other vulnerable populations, or do the bidding of America’s biggest polluters,” said Nathan Willcox, program director for Environment America’s federal global warming program. "We’re thankful that the Senate made it clear yesterday that this dangerous attack on the nation’s health and environment is dead on arrival.”

The fight is likely to continue through different avenues. Several policy "riders" that aim to accomplish the same ends as the House's Energy Tax Prevention Act of 2011 and the failed Senate amendments are now attached to the continuing resolution bill to fund the government.

Environmentalists worry that the Obama administration, which is eager to avert a government shutdown, might compromise on one or more of the riders to the spending bill and permit EPA authority to be weakened. Among those riders are measures to block EPA from regulating greenhouse-gas emissions and to repeal the agency's finding that such gases pose a global warming threat to human health and welfare.

Those riders, as much as money differences, appear to be at the center of the budget impasse. (Many riders are about non-EPA issues, such as NPR funding and Planned Parenthood.) Speaker Boehner Thursday morning said the government funding fight isn't just about money, but also about "common-sense policy restrictions on how taxpayer dollars are spent."

Similarly, Senate majority leader Harry Reid (D) of Nevada, who has been closely involved in budget talks, said it is the policy riders, not the money, holding things up.

"I can see us sitting down at the negotiating table and coming away with an agreement on numbers," Senator Reid said about the negotiations, in a speech on the Senate floor Thursday. "But no one can realistically think that we will walk out of a room and suddenly agree to roll back women's access to health care or protections for the environment."

Those spending bill policy restrictions include riders that would:

• Prohibit EPA use of funds to implement or enforce any statutory or regulatory requirement pertaining to emissions of greenhouse gases, such as carbon dioxide.

• Prohibit the EPA from using any funds to help the United Nations' Intergovernmental Panel on Climate Change.

• Prohibit the EPA from using its funds to develop or enforce any regulation to define coal ash and other residue of power plant combustion as hazardous waste.

• Prohibit funding to create a Climate Service at the National Oceanic and Atmospheric Administration.

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