WASHINGTON — Senate Democrats, including Hawai'i Sens. Daniel K. Inouye and Dan Akaka, failed yesterday to overcome a Republican roadblock on a bill that would have mandated major cuts in emissions of greenhouse gases.

Both senators wanted to push forward with debate on the bill, which became embroiled in a partisan fight over judicial nominations.

"Unfortunately, parliamentary maneuvers over the last few days have used up valuable debate time instead of focusing on the important provisions contained in (the bill)," Akaka said.

The Senate's 48-36 vote fell far short of the 60 votes needed to end a Republican filibuster and move the bill to the Senate floor, essentially killing it for this year.

The Climate Security Act was the first major global warming legislation to pass through the Senate Environment and Public Works Committee. The bill faced an uphill battle in the Senate, where Democrats hold a narrow majority.

President Bush had threatened to veto it, and Republican opponents had complained it would raise gasoline prices and increase taxes. Some advocates of the measure argued it didn't go far enough.

Following yesterday's vote, Democratic leaders and bill supporters vowed to bring up the issue again when a new president and Congress take over next year. Both presidential candidates, Sens. John McCain, R-Ariz., and Barack Obama, D-Ill., said they would have voted to end the filibuster had they been in Washington yesterday.

Inouye, chairman of the Senate Commerce Committee, supported the bill and wanted to add an amendment to increase research into global warming.

"The global climate is changing and these changes will impact people and the ecosystems on which they depend into this century and beyond," Inouye said. "I believe that the single most important factor in our nation's ability to meet the challenges of climate change is the quality of our research and our science."

Questions remain about the speed of the changes, the extent of their impact and their effects on different regions of the United States and the world, Inouye said.

"Robust climate change policy requires robust climate science," Inouye said.

Akaka said that the Mauna Loa Observatory first documented increased carbon dioxide levels in the Earth's atmosphere 30 years ago.

"Sound science continues to substantiate (carbon dioxide's) threat to our health and environment," Akaka said. "I was proud to cast my vote in moving this debate forward and will continue to support a legislative solution."

The bill, co-authored by Sens. Joseph Lieberman, I-Conn., and John Warner, R-Va., calls for a reduction in carbon dioxide and other greenhouse gas emissions by more than 70 percent by 2050.

It also would provide incentives for power plants, factories and oil refineries to reduce emissions. The measure would establish a program to give credits to companies that reduce carbon dioxide emissions. Those companies could sell their credits to help others having a hard time meeting the goal.