As climate change legislation moved higher up on the Congressional agenda last year, so too did the numbers of lobbyists sent to Capitol Hill to influence the debate.

In 2008, some 770 companies and industries groups spent more than $90 million on lobbyists to promote their positions, according to a report released this week by the Center for Public Integrity.

Their sheer numbers are noteworthy, topping about 2,340 -- a 300 percent increase over the past five years. There are now four climate change lobbyists for every member of Congress. Fifteen percent of all D.C. lobbyists devoted some of their efforts to climate change policy during a year when the Warner Lieberman climate change bill, with its goal of reducing greenhouse gas emissions 71 percent below 2005 levels by 2050, failed to muster enough Congressional votes.

The ranks of lobbyists include big names, such as former House Majority Leader Dick Gephart (D-Missouri) and former House Appropriations Committee Chairman Robert Livingston (R-Louisiana), who are both included in a database that can be searched by sector, lobbyist, time frame and company.

The diversity in special interests turning to lobbyists has evolved since 2003, when about 70 percent of business and interest groups lobbying Congress on climate change hailed from carbon-intensive industries, with the remainder comprised of environmental groups.

The field of special interests expanded in 2008, when "virtually every segment of the economy was seeking to weigh in," according to "The Climate Change Lobby."

Among the players:

— Industry Brand-name companies hired lobbyists in 2008 to promote their interests, such as Walmart (more than $7 million), FedEx (nearly $9 million) and General Electric (more than $36,000).

The U.S. Chamber of Commerce and National Association of Manufacturers are longtime opponents; the number of lobbyists representing manufacturing interests alone topped 600 last year. The American Coalition for Clean Coal Electricity spent $10.5 million on at least 15 lobbyists promoting climate legislation that doesn't put coal on the endangered species list.

— Financial services They range from Wall Street banks to smaller firms and would service the blossoming U.S. carbon market as brokers, verifiers, project developers and consultants, with roughly 130 lobbyists in 2008.

— Unions More than 60 climate change lobbyists worked last year to protect the interests of organized labor, such as preventing jobs flying offshore to countries where a price on carbon doesn't exist.

— Cities, counties and municipal agencies Hoping to influence how revenue from a proposed cap-and-trade would be spent, these public entities sent more than 100 lobbyists to Washington, D.C. in 2008.

— Alternative energy In 2003, they numbered less than a half-dozen. Fast-forward to 2008 and there were more than 130 lobbyists representing wind, solar, geothermal, waste-to-energy and waste heat recovery.

— Environmental and health There were less than 50 lobbyists on Capitol Hill working on behalf of NGOs such as the Sierra Club five years ago; their numbers totaled about 185 in 2008. The Environmental Defense Fund spent about $40 million on advocacy last year, or 40 percent of its budget.