Ways which affect the behaviour of the policy maker
There may be at least three ways this uncertainty may affect the behaviour of the policy maker.
a) He may chose mainly those policies which increase the probability of policies holding the office.
b) When it is expected that the policy maker will be replaced by someone with different policy preference (other party) he may chose policy (recall convergence) to influence choice of policy of this rival.
c) If he can affect neither of the above, 'who' will replace becomes important.