Obama says no to summer debates

WASHINGTON - 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.