Senator Barack Obama on Thursday released a list of $740 million in earmarked spending requests that he had made over the last three years, and his campaign challenged Senator Hillary Rodham Clinton to do the same.

The list included $1 million for a hospital where Mr. Obama’s wife works, money for several projects linked to campaign donors and support for more than 200 towns, civic institutions and universities in Illinois.

But as the Senate debated a bill to restrict the controversial method of paying for home-state projects  a measure defeated Thursday evening  Mr. Obama’s presidential campaign also said that only about $220 million worth of his requests had been approved by Congress. And among those that had been killed were his request in 2006 for $1 million for an expansion of the University of Chicago Medical Center, where Mr. Obama’s wife, Michelle, is a vice president.

Mr. Obama’s aides and officials at the hospital said Mr. Obama’s wife had had nothing to do with the request. Campaign officials said he had voluntarily released the list of his earmark requests to underscore his promise to bring greater openness and transparency to government, an issue on which he has tried to put Mrs. Clinton on the defensive.