Of the current colleagues the only ones i see having any chance are Aasif Mandvi and John Oliver who did a fairly decent job last summer as a subsitute for Stewart but he#s got his own show and i don't know if he would be willing to helm the show in the wake of Stewart.
The answer is no. John Oliver loves the amount of freedom he has, HBO lets him do whatever he wants. Also, HBO isn't dumb and just renewed his show through 2017. We get 35 episodes a year, I think there have been two so far this year.