NASHVILLE, Tenn. - Former Vice President Al Gore has collected nearly 300,000 electronic signatures asking Congress to take action on global warming, Gore said in an entry on his Web site Friday. Gore said the signatures demonstrate "that hundreds of thousands of people share my sense of urgency" on climate change. Gore is scheduled to testify before Congress about the issue Wednesday.

"Political will is a renewable resource, and enough already exists to start solving this crisis," Gore said. "We just have to communicate that forcefully to the political leaders of our country."

As of Friday morning, Gore's Web site had received 294,374 signatures. Gore called on supporters to urge friends and family to come up with enough new signatures for him to collect 350,000 by Wednesday.

Gore said members of Congress have "failed to act, because they have not yet faced a sufficient expression of political will on the part of the American people demanding they confront our climate crisis head on."

Gore, who starred in the documentary film "An Inconvenient Truth" about global warming, has said repeatedly he has no plans to join the field of 2008 Democratic presidential aspirants.

But Gore's unwillingness to rule out a run completely has given some activists hope that he might change his mind. Gore lost his home state in the 2000 presidential election to George W. Bush.

Gore said there is a consensus on global warming among scientists.

"The debate on the science has long been over -- except for a diminishing number of skeptics and deniers," he said.

Gore cited findings reported last month by the Intergovernmental Panel in Climate Change reported that global warming is so severe that it will "continue for centuries," leading to a far different planet in 100 years.

The panel, established by the United Nations, concluded that global warming is "very likely" caused by man, meaning more than 90 percent certain.

If nothing is done to change current emissions patterns of greenhouse gases, global temperature could increase as much as 11 degrees Fahrenheit by 2100, the report said.