CEDAR RAPIDS, Iowa —  The battle against global warming means big economic opportunities as well as challenges for the U.S., Democrat Hillary Rodham Clinton said Monday, touting her energy proposals as she campaigned in Iowa.

"For this generation, climate change is our space race," said Clinton, speaking in a cavernous factory with giant wind turbines in the background.

Clinton, who is pursuing the Democratic presidential nomination, is calling for creation of a $50 billion strategic energy fund, coupled with tougher fuel efficiency standards financed in part by $20 billion in "green vehicle bonds." It's part of a package she calls the most comprehensive offered to tackle global warming.

"The climate crisis is also one of the greatest economic opportunities in the history of our country," she said. "It will unleash a wave of innovation, create millions of new jobs, enhance our security and lead the world to a revolution in how we produce and use energy."

Global warming hits particularly hard at the poor, she said.

"One in four low-income families have already missed a mortgage or rent payment because of rising energy costs," Clinton said.

She criticized President Bush for inattention to the issue.

"The president has systematically undermined our path to a clean energy future," she said.

The strategic energy fund would be roughly a third of a 10-year, $150 billion investment called for in her energy package.

The program calls for reducing greenhouse gases by 80 percent from 1990 levels by 2050 and cutting imports of foreign oil by two-thirds by 2030. That import cuts would come through fuel-efficient vehicles, reduced electricity consumption and increased production of alternative fuels, she said.

"It's the biggest challenge we've faced in a generation, a challenge to our economy, our health and our planet," said Clinton. "It's time for America to meet it. It is time to get back into the solutions business."

She estimated her plan would create 5 million new jobs over the next decade, many in rural sections of the country.

Clinton appeared at a factory that produces parts for wind turbines to spell out her proposal, which she said is a centerpiece of her effort to bolster the economy of rural sections of the nation by focusing on developing alternative energy sources.

In earlier speeches leading up to her talk, she has said she would pay for the plan by ending tax subsidies for oil companies, subsidies she argues aren't needed with oil at more than $90 a barrel.