WASHINGTON (CNN) -- Environmental activists are frustrated. They can't get the issue of global warming into the presidential campaign.
So a coalition of environmental groups, led by online magazine Grist.org and Public Radio International's "Living on Earth,'' held the first-ever presidential forum on global warming in Los Angeles on Saturday.
They invited 17 presidential candidates. Three Democrats showed up -- Sen. Hillary Clinton of New York, former Sen. John Edwards of North Carolina and Rep. Dennis Kucinich of Ohio.
They spoke passionately about the crisis.
"We cannot afford to fiddle while the world warms," Clinton said.
And they offered plans to fight global warming.
"You set forth a number of initiatives," Kucinich said.
Do voters care about the issue? They've seen Hurricane Katrina, the California wildfires, the Asian tsunami and a cyclone in Bangladesh.
A CNN/Opinion Research Corporation poll in October found that 66 percent of the public wants the U.S. to take action to reduce greenhouse gases, even if other countries do not act. The poll's margin of error was plus-or-minus 4.5 percent.
Many have seen Al Gore's movie Oscar-winning movie. And heard about his Nobel Peace Prize.
And now they're reading front-page stories about a report from a U.N. scientific panel, released Saturday, that said, "Climate change is "severe and so sweeping that only urgent, global action" can be taken.
The U.N.'s Intergovernmental Panel on Climate Change warned that some of the effects of rising levels of greenhouse gases may already be irreversible.
"The American people are actually hungry to do something as a national community," Edwards told forum participants.
The candidates are pushing the issue.
"I speak about it everywhere that I go to try to get it into the bloodstream of the presidential campaign," Clinton said.
Why is it so difficult? The organizers of the forum blamed the media.
Oh sure, the press covers the issue. CNN ran a week-long series, "Planet in Peril."
But they don't cover it as a campaign issue. Grist.org writer David Roberts argues that's because global warming doesn't fit the conventional model of political coverage.
"It doesn't fit very well into the 'horse race' coverage," said Roberts. "There's not really a hook with one candidate jabbing another or one candidate making a gaffe.
"The press wants conflict, like an anti-war protester confronting Senator Clinton at the global warming forum. Clinton tried to initially ignore the protester and continue with her speech, but then confronted her, asking "were you invited to speak here this afternoon?"
What would it take to get global warming covered as a campaign issue?
"Perhaps if John Edwards' hair caught on fire or something as a result of global warming, then we could get it," said Roberts.
Voters worry about global warming. The candidates have plans for solving global warming.
But the biggest problem may be how to get the issue onto the political agenda.