By Deborah Zabarenko, Environment Correspondent

WASHINGTON, Dec 4 (Reuters) - Duelling videos -- one starring Arnold Schwarzenegger, the other featuring a "typical" U.S. family shivering in an underheated house -- are focusing debate on a Senate bill aimed at cutting climate-warming pollution.

Schwarzenegger, the action star-turned-Republican governor of California, stands in front of a redwood grove and intones, "Climate change: it's a test of leadership." He and two other governors, posed in natural settings, urge viewers to press their senators to approve the so-called Lieberman-Warner bill.

The spot, sponsored by the Environmental Defense Action Fund, is being shown in 17 markets in 11 states and online (http://www.ed.org) in the run-up to an expected vote on the bill in the Senate Environment and Public Works committee. The vote could come on Wednesday.

On the other side of the issue, the U.S. Chamber of Commerce shows a suburban family wearing scarves and coats indoors, huddling under quilts, cooking breakfast eggs over candle flames and commuting to work on foot.

"Climate legislation being considered by Congress could make it more expensive to heat our homes, power our lives and drive our cars," the narrator says. "Is this really how Americans want to live?"

The message, delivered online (www.uschamber.org) and elsewhere and in hourly spots shown at Washington area airports: tell your senators to vote no.

Formally known as the Lieberman-Warner Climate Security Act and sponsored by Senators Joe Lieberman, a Connecticut independent, and John Warner, a Virginia Republican, the bill is the first on climate change to have got this far. Others have stalled before getting to a full committee vote.

The Senate bill aims to set up a federal program to reduce greenhouse gas emissions from the power, industry and transportation sectors by 70 percent by 2050, without cutting economic growth or imposing hardship on U.S. citizens.

To do this, it would set up a cap-and-trade system for the emission of carbon dioxide or other greenhouse gases.

The vote takes place as the world's environmental policymakers gather in Bali, Indonesia, to chart the next steps for a global plan to stem climate change.

FROM CAPITOL HILL TO BALI

The United States is sending a high-level delegation, including James Connaughton, head of the White House Council on Environmental Quality. The United States is now the only major industrialized nation that has not joined the Kyoto Protocol, the 1997 pact that sets binding limits on greenhouse gas emissions. The Bali meeting is meant to chart the way after the Kyoto Protocol expires in 2012.

Concrete policy changes are unlikely immediately from the Bali meeting. Before it started, Connaughton told reporters he hoped for "a clear roadmap that will take us through a negotiating process on an agreed framework."

The Bush administration has consistently opposed mandatory limits on emissions, saying they hurt the economy.

Environmental groups, including Environmental Defense, have cheered this legislation, as has a group called the U.S. Climate Action Partnership, whose corporate members include such carbon-emitting businesses as General Electric, Duke Energy and the Big Three U.S. automakers.

It is opposed by other groups, including the U.S. Chamber of Commerce. On its Web site, the Chamber says it will discourage "ill-conceived climate change policies and measures that could severely damage the security and economy of the United States."

(Editing by Stuart Grudgings)

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