WASHINGTON, D.C. (AP) -- All Republicans except one are boycotting the start of committee debate on a bill to curb greenhouse gases in a protest that the bill's economic costs have not been fully examined.

Republican Sen. George Voinovich of Ohio attended the Tuesday session for 15 minutes to explain the GOP's argument for staying away. He says the tactic "is not a ruse" to block the bill, but concern that widespread impact on the country has not been made clear.

Ohio is especially vulnerable because of its reliance on coal and manufacturing base.

Sen. Barbara Boxer of California, the panel's chairman, argued the EPA already has provided "a full blown economic analysis" and that Majority Leader Harry Reid has promised further studies when the bill is merged with other legislation.

Voinovich says the EPA analysis is inadequate.

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