There was a lot of thought that Clark would endorse Edwards or maybe Dean as a way to create a 2-way race. Kerry, as being stronger on national security issues, may have always been Clarks preferred candidate. However, I realize now that Clark
had to endorse Kerry for the future of his political career.
Clark is clearly from Arkansas... so that is where he would have to run for a position. However, thanks to Mark Pryor and Blanche Lincoln... the Arkansas Senate seats are going to be safely Dem for quite a while. The only House Republican, John Boozman is already being given quite a race by Jan Judy, and Clark's name is a bit big for a house seat anyways. That leaves the governorship open in 2006, but Clarks strong point is definitely not the domestic policy necessary to win that election.
So, in short... if Clark wants to continue his political career anytime soon, he needs a Cabinet position in the next administration. Sheer realism (cynicism?) dictates that he get close to the likely Dem nominee now for that to happen.