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.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.
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.