In case any of the other 24 fans out there haven't seen it, here's the preview for season six. The clip seems to show and his Wikipedia biography says that Wayne Palmer is the new President. Though I can tolerate a certain degree of ridiculousness - I'm struggling with how they'll make the former president's brother into the President of the United States.
From my memory of past seasons, Wayne was his brother's chief of staff which is an important position but not one that alone qualifies an individual for the White House. I can't remember a ton of other biographical/background details besides the service in the Marines that Wikipedia mentions but it seems the 24 writers are stretching our limits of imagination more than a little too far if they think they can make Wayne become president without adding some more political accomplishments (which would be difficult considering the next season of 24 usually occurs just a couple of years after the last one).
Not to mention the whole affair with Milliken's wife and him being at the crime scene when Milliken's wife shot Sherry before turning the gun on herself.