People around the country accused Denver of embracing a "crackpot" scheme to fight global warming Monday, after the city's plan drew widespread attention on the Internet.

The reaction was to a Rocky Mountain News story that detailed some of the proposals in Denver's Climate Action Plan, which aims to cut the city's output of gas emissions linked to global warming.

The plan includes several controversial ideas, including making residents who use large amounts of electricity and natural gas pay higher utility fees, boosting insurance rates for people who drive long distances and mandating that homes be energy efficient before they can be sold.

After the online RockyMountainNews.com version of the story was posted as the lead item on Drudgereport.com, the phones started ringing at Mayor John Hickenlooper's office. Many of the calls were from people accusing the city of embracing a radical environmental agenda.

"We've gotten a bunch of phone calls, but nothing like a good snowstorm," Hickenlooper said.

E-mails to the city and the Rocky from around the country called the plan "crackpot," "loony" and even "stupid."

Hickenlooper said the proposals are just ideas at this point but that he believes the majority of Denver residents want the city to take strong action against global warming.

"According to most polls, 70 percent of the people in Colorado recognize there is global warming," he said. "I think most people are very concerned about this issue because the consequences are so catastrophic."

The mayor said he would listen to public reaction before moving ahead but that he aims to have a plan in place by the end of the year.

"It's the community's job to go forward and look at this list and work our way through it," he said.

Some of the proposals in Denver's plan that might sound radical to residents are already in place in other states. California already charges heavy users of electricity higher rates.

Denver city councilwoman Kathleen MacKenzie said she admires Hickenlooper for pushing the plan.

"The mayor is willing to use his popularity to ask people to do difficult things," she said. "I hope people are ready to take this on."

A spokeswoman for the Home Builders Association of Metro Denver said that group hasn't taken a position on Denver's proposal to enact energy efficiency standards for new homes.

She noted the association started a "Built Green" program in 1995 that makes homes more energy efficient and so far includes 33,000 new houses.