(Adds EPA reaction in the 13th paragraph.) By Siobhan Hughes and Corey Boles Of DOW JONES NEWSWIRES WASHINGTON (Dow Jones)--U.S. Senate Democrats, responding to the environmental wing of the party's base, held together and narrowly fended off a Republican-led effort to overturn the first-ever nationwide regulations to limit greenhouse-gas emissions. By 53-47, the U.S. Senate blocked a "disapproval resolution" targeting a U.S. Environmental Protection Agency finding that rising concentrations of greenhouse gases in the atmosphere endanger the public. The finding, issued last year, is the basis for new rules to curb greenhouse-gas emissions from cars, trucks, power plants and other facilities. Businesses have warned that higher costs and job losses will result. The Republicans needed 51 votes to advance the resolution and begin the process of stopping the EPA. "This was in many ways a turning point for the United States Senate," declared Sen. Barbara Boxer (D., Calif.), after the vote. Earlier, in a line of attack that Republicans view as unfair and that Democrats are increasingly pushing, Boxer brought up the BP PLC (BP, BP.LN) oil spill in the Gulf of Mexico--one of the worst in U.S. history--as evidence of "what too much carbon-based pollution does in water; what it does to our shorelines; what it does to our beaches; what it does to our wetlands." With the EPA regulations due to take hold starting in 2011, lawmakers from states that rely on fossil fuels are growing anxious. In a sign of the concern, Sen. Jay Rockefeller (D., W.Va.) broke ranks with his party and joined Republicans in an attempt to block rules that would disadvantage fossil fuels such as coal, which underpins his state's economy. He was one of six Democrats to side with Republicans. Sen. Lisa Murkowski (R., Alaska) led the charge against the EPA, calling its rules an "unprecedented overreach" into "the affairs of Congress." She warned that the costs of the EPA's regulations are unknown, since the agency hasn't yet specified what counts as the best technologies to control emissions from stationary sources. Under the EPA rules, starting in January 2011, large facilities that undergo modifications will have to prove they are using the best available technologies to control greenhouse gases in order to receive needed regulatory permits. By July 2011, any new, large facilities will be subject to greenhouse-gas permitting requirements. Motor vehicles face separate fuel-efficiency requirements, though the rules are also the subject of a separate pact between the Obama administration and the auto industry reached last year. The White House began defending the EPA regulations in earnest this week, threatening to veto the Republican disapproval resolution and arranging personal appeals to individual lawmakers. EPA Administrator Lisa Jackson took a public role, writing that the resolution would "allow big oil companies, big refineries and others to continue to pollute without any oversight or consequence." On Thursday, the Obama administration also drove home a message that greenhouse-gas rules can create jobs, announcing more than $700 million for "clean energy" projects. The funding included $612 million for projects to capture and store carbon-dioxide emissions, something favored by Sen. Byron Dorgan (D., N.D.). Dorgan has reservations about the EPA's greenhouse-gas rules but avoided expressing those concerns Thursday, sticking with his party and voting against the disapproval resolution. Even so, the concerns point to the cloud that remains over the EPA rules even with the defeat of Murkowski's resolution. Dorgan as well as Sens. Jim Webb (D., Va.) and Kent Conrad (D., N.D.) said they support an alternative approach advanced by Rockefeller to suspend EPA rules on power plants, factories and other stationary sources for two years. Webb signaled the intensity of his position on the Senate floor, announcing that he would "regretfully" oppose the Murkowski resolution. It wasn't clear whether Senate Majority Leader Harry Reid (D., Nev.) has agreed to bring such an alternative up for a vote. "I don't know if Harry has made any promises along those lines," Sen. Dick Durbin (D., Ill.), the No. 2 Democrat in the Senate, told a reporter Thursday. A 2007 Supreme Court decision had ordered the EPA to determine whether rising concentrations of carbon dioxide in the atmosphere posed a threat to the public. The EPA chief issued an endangerment finding last year, saying higher gas concentrations create a risk of more flooding, more frequent and intense heat waves and rising sea levels. The finding was the basis for the first-ever federal greenhouse-gas regulations for both cars and industrial sources such as power plants. "We managed to avoid taking a big step backwards," EPA spokeswoman Adora Andy said after Thursday's vote. The Obama administration has maintained that regulations are necessary because the U.S. Congress has failed to act. Though the U.S. House of Representatives cleared an energy and climate bill last year, action has stalled in the U.S. Senate, where lawmakers from coal, manufacturing and oil states have refused to go along. With the BP oil spill fresh in the minds of voters, U.S. politicians are trying to revive energy legislation. U.S. President Barack Obama said last week that he will find votes to pass an energy bill in coming months, saying the disaster shows the pitfalls of the nation's reliance on traditional fossil fuels. The Obama administration has been supported by groups such as Americans United for Change, which pounded on Sens. Scott Brown (R., Mass.) and Susan Collins (R, Maine). The group bought local television ads that highlight the BP oil spill and suggest Republicans who vote for the resolution believe the environment "hasn't been polluted enough." The two Republicans resisted the pressure, putting Republicans unanimously in favor of overturning the EPA rules. Though some Republicans, such as Sen. Jim Inhofe (R., Okla.), say climate change is a hoax, others feel the EPA has gone too far and is assuming powers that belong to Congress. Pressure also came from business groups. The U.S. Chamber of Commerce made clear that it would watch how lawmakers voted, saying the vote would be factored into a scorecard on lawmaker records on business issues. The group has separately challenged the legality of the EPA's greenhouse-gas endangerment finding. -By Siobhan Hughes, Dow Jones Newswires; 202-862-6654; [email protected] -By Corey Boles, Dow Jones Newswires; 202-862-6601; [email protected] (END) Dow Jones Newswires June 10, 2010 17:55 ET (21:55 GMT)