Senator John McCain’s campaign manager was paid more than $30,000 a month for five years as president of an advocacy group set up by the mortgage giants Fannie Mae and Freddie Mac to defend them against stricter regulations, current and former officials say.

Mr. McCain, the Republican candidate for president, has recently begun campaigning as a critic of the two companies and the lobbying army that helped them evade greater regulation as they began buying riskier mortgages with implicit federal backing. He and his Democratic rival, Senator Barack Obama, have donors and advisers who are tied to the companies.

But last week the McCain campaign stepped up a running battle of guilt by association when it began broadcasting commercials trying to link Mr. Obama directly to the government bailout of the mortgage giants this month by charging that he takes advice from Fannie Mae’s former chief executive, Franklin Raines, an assertion both Mr. Raines and the Obama campaign dispute.

Incensed by the advertisements, several current and former executives of the companies came forward to discuss the role that Rick Davis, Mr. McCain’s campaign manager and longtime adviser, played in helping Fannie Mae and Freddie Mac beat back regulatory challenges when he served as president of their advocacy group, the Homeownership Alliance, formed in the summer of 2000. Some who came forward were Democrats, but Republicans, speaking on the condition of anonymity, confirmed their descriptions.

“The value that he brought to the relationship was the closeness to Senator McCain and the possibility that Senator McCain was going to run for president again,” said Robert McCarson, a former spokesman for Fannie Mae, who said that while he worked there from 2000 to 2002, Fannie Mae and Freddie Mac together paid Mr. Davis’s firm $35,000 a month. Mr. Davis “didn’t really do anything,” Mr. McCarson, a Democrat, said.

Mr. Davis’s role with the group has bubbled up as an issue in the campaign, but the extent of his compensation and the details of his role have not been reported previously.

Mr. McCain was never a leading critic or defender of the mortgage giants, although several former executives of the companies said Mr. Davis did draw Mr. McCain to a 2004 awards banquet that the companies’ Homeownership Alliance held in a Senate office building. The organization printed a photograph of Mr. McCain at the event in its 2004 annual report, bolstering its clout and credibility. The event honored several other elected officials, including at least two Democrats, Gov. Edward G. Rendell of Pennsylvania and Representative Artur Davis of Alabama.

In an interview Sunday night with CNBC and The New York Times, Mr. McCain noted that Mr. Davis was no longer working on behalf of the mortgage giants. He said Mr. Davis “has had nothing to do with it since, and I’ll be glad to have his record examined by anybody who wants to look at it.”

Asked about the reports of Mr. Davis’s role, a spokesman for Mr. McCain said that during the time when Mr. Davis ran the Homeownership Alliance, the senator had backed legislation to increase oversight of the mortgage companies’ accounting and executive compensation. The legislation, however, did not seek to change their anomalous structure as private companies with federal support.

The spokesman, Tucker Bounds, also noted that the Homeownership Alliance included nonprofit organizations like Habitat for Humanity and the Urban League. “It’s not controversial to promote homeownership and minority homeownership,” Mr. Bounds said. More than a half-dozen current and former executives, however, said the Homeownership Alliance was set up mainly to defend Fannie Mae and Freddie Mac by promoting their role in the housing market, and the two companies paid almost the entire cost of the group’s operations.

“They were financed largely, possibly exclusively, by Fannie and Freddie,” said William R. Maloni, a Democrat who is a former head of industry relations for Fannie Mae. “We thought it would be helpful to have someone who was a broadly recognized Republican to be the face of the organization, and that person became Rick Davis.” Mr. Maloni added, “Rick, for that purpose, turned out to be quite good.” (Several executives said Mr. Davis’s compensation was not unusual for the companies’ well-connected consultants.)

The federal bailout of the two mortgage giants has become an emblem of what critics say is the outdated or inadequate regulatory system that allowed the financial system to slide into crisis this summer.

At the time that Fannie Mae and Freddie Mac recruited Mr. Davis to run the Homeownership Alliance in 2000, they were under new pressure from private industry rivals and deregulation-minded Republicans who argued that the two companies’ federal sponsorship gave them an unfair advantage and put taxpayers at risk. Critics of the companies had formed their own Washington-based advocacy group, FM Watch. They were pushing for regulations that would deter the companies from expanding into new areas, including riskier and more profitable mortgages.

Mr. Davis had recently returned to his lobbying firm from running Mr. McCain’s unexpectedly strong 2000 Republican primary campaign, which elevated Mr. McCain’s profile as a legislator and Mr. Davis’s as a lobbyist.

“You can say what you want about free-market distortions, but people like the system because it gets them into houses cheap,” Mr. Davis said to Institutional Investor magazine in 2000, adding that he would run the advocacy group out of his Alexandria, Va., lobbying firm.

The organization also hired Public Strategies, a communications firm that included former Bush adviser Mark McKinnon. Mr. Davis wrote letters and gave speeches for the group. In April 2001, he sent out a press release headlined, “It’s Tax Day — Do You Know Where Your Deductions Are? For Most Americans, They’re in Your Home.”

But by the end of 2005, Fannie Mae and Freddie Mac were recovering from accounting problems and re-examining costs, former executives said. The companies decided the Homeownership Alliance had outlived its usefulness, and it disappeared.

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