At a tense hearing of the Senate Environment and Public Works Committee that most Republicans boycotted, Voinovich, R-Ohio, urged panel Democrats to postpone voting on the bill for at least a month until the U.S. Environmental Protection Agency completes a detailed analysis of the effect the bill would have on the economy.

An emotional Voinovich insisted that "this is not something on my part that I am trying to con you out. This is a really important issue. I have put hours into it. I do want to work on a bipartisan basis."

Appealing to Sen. Barbara Boxer, the committee chairwoman, Voinovich said, "Asking for an EPA analysis is not a stalling tactic. This is not a ruse to prevent the committee from marking up a climate bill."

Voinovich, the only one of seven committee Republicans at the hearing, spoke for about 15 minutes. After Boxer said the panel would delay only for a day before beginning to amend the bill, Voinovich left the hearing room.

"We are not rushing," said Boxer, D-Calif. "We are taking our time here."

Boxer said that once the panel approves the bill, Senate Majority Leader Harry Reid, D-Nev., will delay a floor vote until the EPA has provided a detailed analysis. She said, however, that the EPA already had provided the committee with a "full-blown economic analysis" of the climate-change bill.

But Voinovich rejected Boxer's offer, saying, "These are not issues that can be simply fixed on the Senate floor. Indeed, the very reason we employ a committee process in the drafting of legislation is so major problems can be resolved prior to moving to the floor."

At least some environmentalists feared that Voinovich earned the better of the exchange.

Frank O'Donnell, president of the Washington-based Clean Air Watch, said some senior Democrats think committee Democrats "are screwing it up because they wanted a debate on how you create jobs through this legislation. Instead, the story is about the boycott. So I would give that round to the Republicans for taking the Democrats off their game."

But Daniel Weiss, a senior fellow at the Center for American Progress Action Fund, said, "By the Republican senators failing to show up for work, they have reinforced their image as the party of no solutions to our energy challenges. That's why it clearly was nothing more than a stalling tactic. All the Republican senators (on the committee) have indicated they will be opposed to this bill."

Boxer has enough committee votes to amend and approve the bill, eventually, with or without any Republicans. But O'Donnell said that if she has to push it through while Republicans boycott, "then it really taints the bill and really makes it that much harder for a good bill to be enacted."

Because of deep divisions among many Democrats, Boxer almost certainly does not have the 60 votes necessary at this point to end an all-but-certain Republican filibuster when the bill in its current form reaches the floor.

Among Senate Democrats who have raised objections to the current bill is Sherrod Brown of Ohio.

The bill is aimed at dramatically reducing greenhouse gases during the next 30 years. It would achieve those reductions through a market-based system known as cap-and-trade, which is designed to give power companies and factories financial incentives to limit emissions of carbon dioxide.

For example, each utility plant or factory would need a permit for the carbon dioxide it emits. Factories that dramatically reduce emissions could sell the permits they no longer need to other factories or power plants unable to achieve the reductions on their own.

Dispatch Washington Bureau Chief Jonathan Riskind contributed to this story.

jtorry@dispatch.com