Obama backs away from debate challenge

? Democratic candidate Barack Obama on Saturday backed away from rival John McCain’s challenge for a series of joint appearances, agreeing only to the standard three debates in the fall.

In May, when a McCain adviser proposed a series of pre-convention appearances at town hall meetings, Obama said, “I think that’s a great idea.” In summer stumping on the campaign trail, McCain has often noted that Obama had not followed through and joined him in any events.

Obama’s reversal on town hall debates is part of a play-it-safe strategy he’s adopted since claiming the nomination and grabbing a lead in national polls. Advisers to the Illinois senator, speaking on condition of anonymity because they are not authorized to discuss strategy, say Obama is reluctant to take chances or give McCain a high-profile stage now that Obama’s the front-runner.

On Saturday, in a letter to the Commission on Presidential Debates, Obama campaign manager David Plouffe said the short period between the last political convention and the first proposed debate made it likely that the commission-sponsored debates would be the only ones.

McCain’s campaign disparaged Obama for backing off. McCain has not yet formally agreed to the commission-sponsored debates, but the McCain campaign says he plans to.

“We understand it might be beneath a worldwide celebrity of Barack Obama’s magnitude to appear at town hall meetings alongside John McCain and directly answer questions from the American people, but we hope he’ll reconsider,” spokesman Brian Rogers said.