From Chris Mathews:

MEMPHIS, Tenn. – It’s early on at the Southern Republican Leadership Conference down here, but already we’ve learned some big news.
Sources tell me that Sen. John McCain, R-Ariz., plans to shock his supporters tonight by asking them to NOT vote for him in the presidential straw poll that will be conducted by The Hotline on Saturday.
Instead, McCain will urge his followers to write in President Bush’s name.