Why did Al Qaida endorse McCain?

W/ all the talk about O'bama and self proclaimed terrorist Billy Ayres, Why did the people responsible for 9/11 endorse John McCain for president? McCain said the other day he is the only person who knows where Osama is and hes the only one who can catch him, but if he dies his stewardess Palin is more than qualified to take over. Is this what he means by being a maverick?