The right of election of the surviving spouse may be exercised only during the spouse's lifetime; provided the personal representative of the spouse's estate shall succeed to the surviving spouse's rights under a right of election exercised by the spouse. In the case of a protected person, the right of election may be exercised only by order of the court in which protective proceedings as to the protected person's property are pending, after finding that exercise is necessary to provide adequate support for the protected person during a probable life expectancy. For purposes of this section a “protected person” is a minor or other person for whom a guardian or trustee has been appointed or other protective order has been made.