The Sierra Club today launches a bid to counteract what it calls the dangerous influence of Koch Industries owners David and Charles Koch, as the brothers prepare to meet with conservative contributors in California.

Using social media sites Facebook and Twitter, Sierra Club will ask its 1.4 million followers to post their "dislike" of the Koch brothers and publish a series of claims about the brothers and the company, including that they deny climate change is occuring, that they have outspent Exxon Mobil Corp. in fighting clean energy legislation and that Koch Industries emits "eight times more air pollution than BP."

Wichita, Kan.-based Koch Industries is involved in oil refining, minerals and manufacturing of fertilizers and chemicals.

"A lot of people don't know who the Koch brothers are," said Sierra Club spokeswoman Kristina Johnson. "It's pretty scary once you find out how much power they have and how much damage they have done and are capable of doing.

"It's worrisome to us that you have these billionaires who have so much power to determine environmental regulations and to stop protections of clean air and water."

The Sierra Club campaign comes as the brothers meet near Palm Springs, Calif., for an annual fundraising weekend. Politico reported yesterday that the resort gathering will draw "200 wealthy businessmen, Republican politicians and conservative activists for a semiannual conference to raise millions of dollars for the institutions that form the intellectual foundation -- and, increasingly, the leading political edge -- of the conservative movement."

Spokeswomen for Koch Industries did not respond to requests for comment, but a company liaison offered a response from the conference spokeswoman.

"This conference brings together some of America's greatest philanthropists and most successful business leaders whose companies have created millions of real jobs," conference spokeswoman Nancy Pfotenhauer said. "Attendees will discuss solutions to our most pressing issues and strategies to promote policies that will help grow our economy, foster free enterprise and create American jobs. We respect all Americans' rights to free speech and to peaceably assemble, and we hope that any protesters will respect the community and not cause an inconvenience for residents."

Common Cause is planning a Sunday protest outside the Rancho Las Palmas resort in Rancho Mirage, Calif.

The brothers are major political contributors, Center for Responsive Politics data show. Koch Industries in the 2010 election cycle gave $1.7 million to Republican candidates and $150,500 to Democratic candidates. They have contributed to some tea party candidates. They also spent $12.3 million lobbying in 2009 and $6 million in the first nine months of 2010.

They also started the Americans for Prosperity Foundation, which the Center for Responsive Politics reports spent $1.3 million in the 2010 election cycle, targeting nearly all Democratic candidates. Many of those who were incumbents lost their seats, including Rep. Rick Boucher (D-Va.), a member of the House Energy and Commerce Committee, and Rep. Earl Pomeroy (D-N.D.), who was on the House Agriculture Committee.

The Sierra Club hopes that pressure from social media sites will "make it more difficult for lawmakers to take money from the Koch brothers," Johnson said.