Fannie Mae spent $87 million for an advertising campaign that helped thwart efforts by Congress in 2003 and 2004 to create a tougher regulator for the government-chartered company, a University of Pennsylvania study says.

Fannie Mae, the largest source of money for American home mortgages, paid for 10,797 print and television ads during the period, the university’s Annenberg Public Policy Center at Philadelphia said.

The ads were concentrated in the Washington, D.C., area and aimed at convincing the county’s 100 senators, 435 representatives, and their staffs about the importance of Fannie Mae to financing homeownership, the study says.

“The ads are like having first-strike nuclear capability,” Kathleen Hall Jamieson, director of the center, said yesterday in an interview. “You don’t have to use it nationally or in lawmakers’ home districts, but it says your capability is there.”

The company’s outlay, including the nonprofit Fannie Mae Foundation, was 22% of the $404.4 million spent by all companies and groups on “issue advertising” aimed at Congress, and more than double the $33.5 million spent by GlaxoSmithKline, the second-largest ad buyer. Freddie Mac, a smaller rival to Fannie Mae, spent $7.6 million.

“The company has significantly cut back its advertising for 2005,” a Fannie Mae spokesman, Brian Faith, said. He declined to provide a dollar figure for the ad budget.

The ad blitz helped stall an effort in Congress, backed by the Bush administration, to create a regulator with authority to alter capital standards, reject new lines of business, and oversee other operations at the companies, the study said.

The companies said such a regulator would hamper their federal mission to expand homeownership. Their rivals, including a coalition of financial companies called FM Policy Focus, spent nothing on issue advertising, the report said.

The effort to toughen regulation gained momentum this year because of accounting errors at the companies. Fannie Mae said accounting mistakes from 2002 until mid-2004 may require it to restate at least $8.4 billion in earnings. Freddie Mac, based in McLean, Va., disclosed in 2003 that it understated profits from 2000 until 2002 by $5 billion in an effort to reduce earnings volatility.

Fannie Mae’s board in December ousted its chairman and chief executive, Franklin Raines, after the Securities and Exchange Commission ruled that the company made mistakes in accounting for contracts designed to protect its mortgage portfolio from swings in interest rates.

A new regulator was endorsed last week by Federal Reserve Chairman Alan Greenspan and Treasury Secretary Snow, who called on Congress to create a stricter overseer that would dispel concerns about accounting mistakes and reduce the risk the enterprises will trigger financial market instability. Both the House of Representative and the Senate are again considering creating a tougher regulator.

Fannie Mae and Freddie Mac, which own or guarantee almost half the $7.6 trillion mortgage market, make money on the difference between the returns on the mortgage assets they buy from lenders and their financing costs.

The enterprises have more than $1.7 trillion of debt, exceeding both France and Britain. Fannie Mae is the second largest debtor in America after the Treasury, with $911 billion outstanding. Its mortgage portfolio totaled $875.2 billion in February. Freddie Mac’s totaled $654.8 billion.

The Annenberg report quoted a Fannie Mae TV ad saying, “We built something special in America, the finest home financing system in the world, opening the doors to home ownership all across our country. Showing a couple grinning and hugging in front of a house, the ad ends by saying, “We believe that every American family deserves a special place they can call home.”

Fannie Mae intends this year to “sharply” cut spending on advertising and lobbying, the Washington-based company said in a February 23 statement. The Homeownership Alliance, a coalition of housing groups created by Fannie Mae and Freddie Mac, paid $1.3 million for ads in 2003 and 2004, the Annenberg Center said.

A Fannie Mae spokesman, Chuck Greener, on April 5 referred to the company’s view toward a new regulator in an e-mailed release, saying “we will be reviewing a new regulatory bill and remain committed to working constructively and cooperatively.”

Freddie Mac spokeswoman Sharon McHale declined comment.

Organizations aren’t required to report their spending on issue advocacy so the Annenberg Center estimated the advertising expenditures, the center’s director, Hall Jamieson said.

For print advertising, the center used the prevailing advertising rate for the amount of space purchased. For TV advertising, it hired Campaign Media Analysis Group to obtain the storyboards and estimate the cost of airtime, Hall Jamieson said. Some of the cable TV advertising may also have appeared outside the Washington area, she said.

The Annenberg estimate doesn’t include any discount Fannie Mae might have received for buying ad space at a high volume, said Erika Falk, the research director for the report.

Fannie Mae was given a “chance to correct” the estimates but didn’t do so, Ms. Hall Jamieson said.