DURHAM, N.H. - When President Obama makes a campaign stop here this afternoon, he'll have an anonymous donor to thank for defusing what had been a growing controversy over the cost of the presidential visit to local taxpayers.

Durham officials announced Sunday that an unidentified town resident offered $20,000 to cover the extra police and fire services deployed in conjunction with Obama's speech at Oyster River High School. The town had sought reimbursement from the president's campaign, which demurred.

"We have more than enough civic work on our plate," Durham council chairman Jay Gooze said in a statement. "To be clear, our request came from the basic responsibility that a local government has to its residents to ensure that expenses outside our approved budget are recovered in a fair and equitable manner."

Most localities visited by the president on official and political business usually absorb the cost of deploying extra local public safety services to support Secret Service. But given budget concerns, officials here decided to request reimbursement given the political nature of the event.

Obama campaign aides said local public safety staffing and operations were out of their control and thus costs could not be reasonably assigned to them.

"As a private organization, OFA does not participate in security or traffic control planning. All such decisions, including their impact on costs incurred by federal, state or local governments, are exclusively within the control of the appropriate government officials," Obama for America chief operating officer Ann Marie Habershaw wrote in a letter to Durham town manager Todd Selig on June 23.

"Should there be a question about the allocation of expenses among the cooperating authorities, we assume that it should be directed to the U.S. Secret Service," she said.

At a press conference Sunday, Gooze thanked the donor for resolving the issue. "The donor wanted us to make public his/her sentiment that our town had done the right thing in asking the campaign to do its part," he said. "We are grateful for this generous offer."

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An emergency council meeting that had been planned for this morning to publicly debate the cost of the president's trip was cancelled, averting what could have been a distracting sideshow to Obama's event.

But the controversy is not entirely over. The pro-Republican advocacy group Americans for Prosperity has filed a "right to know" request with the town administrators seeking to reveal the identity of the donor.

"The people of Durham have a right to know the identity of this anonymous donor and what his or her intentions are in giving this significant sum of money," said Corey R. Lewandowski, State Director of Americans for Prosperity-New Hampshire. "The donor may have business pending before the town or may be trying to skirt [Federal Election Commission] law, which precludes this sort of donation."

Durham, home to the University of New Hampshire, is a majority Democratic area. Officials and local residents said they welcomed Obama but were concerned about costs.