Former U.S. Vice President Al Gore said he can do more to fight global warming as a private citizen than he could working as a government official even if Barack Obama wins the presidency.
``My own best role is to try to bring about a sea change in public opinion,'' Gore said today on NBC's ``Meet the Press.'' ``Policy makers who know the right thing to do run up against a wall set up all around them by the lobbyists and the special interests,'' he said.

James Carville, a senior strategist for former President Bill Clinton, has said Gore would be in the best position to fight climate change as a vice president or energy czar. Gore today said he couldn't be talked into a government post.

Earlier this week Gore called for the U.S. to produce all its electricity from renewable energy and ``carbon-free sources'' within 10 years. The declining cost of solar, wind and geothermal power, combined with rising oil prices, demonstrates the benefits of renewable energy, he said at a speech in Washington.

The Alliance for Climate Protection, a group Gore founded, estimates it will cost from $1.5 trillion to $3 trillion to transform the U.S. to using only clean electricity sources.

Gore, 60, who won the Nobel Peace Prize last year, has focused on global warming since losing the 2000 presidential election to George W. Bush. In April, the Alliance for Climate Protection, announced it would spend $300 million on a three- year advertising campaign aimed at pushing for new energy policies.

``Our current course is unsustainable,'' Gore said today. ``The climate crisis has to push us as Americans to take this issue out of the old partisan squabbling.''

The U.S. Senate, which is controlled by Democrats, failed to pass legislation last month that was designed to reduce greenhouse-gas emissions. Gore said his party has struggled to fight climate change because it only has a 51-49 Senate majority.

``Congress ought to do more,'' he said. ``When you don't have 60 votes in the Senate to overcome filibusters, nothing can happen.''