The F.C.C. has largely adopted recommendations from Google on set-top-box reforms, the cable and telecom companies said. AT&T’s senior vice president for external affairs, Jim Cicconi, has called the plan the “Google proposal.” The cable companies also said the F.C.C.’s broadband privacy proposal would be much stronger than any restrictions placed on web companies.

So the cable industry has harnessed its vast lobbying resources in Washington to fight back.

In the first quarter, cable and telecom companies spent $22 million on lobbying, ranking 11th by industry, according to the OpenSecrets website, run by the Center for Responsive Politics. While the spending did not increase from a year earlier, much of the money has gone toward fighting F.C.C. proposals like the set-top-box rules, with nearly $2 million paid just to outside lobbyists in the first quarter to work against the proposal, according to federal disclosures.

AT&T, Comcast, Verizon and the N.C.T.A. are also practicing softer forms of lobbying — such as sponsoring studies and consultants who write op-ed articles — that cannot be easily traced, analysts and public interest groups like Free Press, which supports several broadband regulations, say.

The industry’s focus has been on helping members of Congress write letters of opposition to the F.C.C., including the critical letter shown by Mr. Rush’s staff. The association said an employee contributed “minor suggestions” to the letter from Mr. Rush. Mr. Rush’s spokeswoman, Debra Johnson, said the N.C.T.A. edits “did not change the substance of the letter” and added that the congressman had a history of standing up for consumer protection issues.

Some consultants for cable companies have also criticized the F.C.C. proposals. In March, Henry Waxman, a former Democratic congressman from California, wrote a harsh op-ed in The Hill slamming the set-top-box plan, without disclosing that he was a consultant for Comcast and had business ties to the N.C.T.A.

Mr. Waxman and other lawmakers who have been critical of the set-top-box plan said they were not financially motivated to weigh in on the issue.

“I don’t represent clients on issues I don’t believe in,” Mr. Waxman said.

The cable industry has also responded with a new lobbying group, the Future of TV Coalition, which has been joined by media and movie companies as well as labor unions. The group was formed on the day the F.C.C. announced the set-top-box proposal, with a website and statements from companies against the idea. So far, the organization has helped generate 300,000 comments opposing the set-top-box plan through a tool on its website that sends complaints directly to the F.C.C.