WASHINGTON — Losing key members and facing political headwinds, the U.S. Chamber of Commerce spent a record $34.7 million in the third quarter lobbying against the Obama administration's proposals to overhaul energy policy, financial regulation and health care.

The chamber's money paid for more than a dozen lobbyists to visit Congress, the White House and agencies from Agriculture to Treasury. Most of the chamber's positions — free trade, unfettered credit card lending, Cash for Clunkers rebates — enjoy broad support among the chamber's diverse corporate members.

The chamber's lobbying agenda encompasses virtually any issue that affects business — so the group has a stance on virtually every issue. Debates on far-reaching effects, like health care, often occupy the most attention. But the chamber disclosure also shows the group devoted serious resources to issues important to a smaller number of members — Internet taxation, immigration enforcement and forcing children to speak English.

However, on one broad issue considered critical to the Obama administration's success, the chamber's anti-regulatory postures created a rift. On the question of how to address climate change, the chamber has seen a growing number of companies defect. They say the organization doesn't speak for them when it denies global warming and lobbies against climate change legislation.

Early and high-profile departures included Apple Inc., Exelon Corp., Pacific Gas and Electric Co. and the Public Service Co. of New Mexico. Yesterday, Mohawk Fine Paper, a privately-held paper manufacturer based in Cohoes, N.Y., joined them.

Chamber defenders said the companies were protecting their own economic interests and shifting with the political winds.

But George Milner, Mohawk's vice president for environmental affairs, said it hurts the company's credibility as an advocate for environmental protection when it belongs to an organization that vigorously opposes action on climate change.

A chamber spokesman didn't immediately respond to a request for comment yesterday on Mohawk's decision.

White House officials have seized gleefully on the anti-chamber backlash, caricaturing the group as out of touch and unable to negotiate the new political climate.