There is an excellent rundown at Daily Kos on the most likely replacement for Ashcroft, Alberto Gonzales. He is currently the White House chief consul. The administration's lawyer that is. He is also the one who signed off on the White House's attempts to circumvent, and now to eliminate U.S. adherence to the Geneva Convention.
Update: Oh, I forgot to mention that he was also the general counsel for Enron. He also testified before the grand jury in the Valerie Plame investigation. (Lest we forget, the special prosecutor, Patrick Fitzgerald is still hunting down all the odds and ends over who exposed Plame as a CIA "operative". An investigation that is finding fingerprints in the White House.)
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