Federal lawmakers and representatives from Germany's 16 states will elect the largely ceremonial head of state next February. President Joachim Gauck, a former pastor and East German pro-democracy activist with no party affiliation, enjoys support from most mainstream political parties.
However, he's already Germany's oldest president at 76 and has left open whether he will run again. If he doesn't, that would force Merkel and rivals into a politically charged search for a successor ahead of a parliamentary election later next year.