Dreams from My Ghostwriter?

There are claims that Bill Ayers made essential contributions to Obama's auto(?)biography (H/T: Dinocrat).

Is there pattern-recognition software that could help to reach a conclusion? I seem to recall hearing about programs that test for plagiarism by professional authors or copying/plagiarism by students.

(It might be too late in the game for something like this, even if shown to be true, to turn the race around. It could have been a difference-maker if McCain had been running a coherent campaign instead of indulging in a series of stunts: some brilliant and others erratic, discomfiting, arguably self-disqualifying. Still, 'a week is an eternity in politics'.

I want Obama to lose, but McCain's temperament worries me and I question whether he has campaigned well enough to deserve to win. And a society that appoints a Bill Ayers to be a Distinguished Professor of Education at a state university...what does it deserve?)

Addendum. This looks like a job for a forensic linguist (H/T: Althouse commenter Pogo) or a stylometer: a courageous one, given how Joe the Plumber is being pilloried. In fact, since free software is available, I wonder if Rathergate debunker Charles Johnson is cranking away.

Addendum 20090429. The creator of the above stylometric software does not believe that Ayers ghosted 'Dreams from My Father'.

Addendum 20131203. The above link is dead, but not the post; see here.