Target production

Question:

   As you thank one of the polling staffers for your visit, she tells you that of the 862 people called that day, the call center reached 256 residents in McGovern’s target population. She says, “I appreciate what great attention you have paid to our work. Given the information you have gathered today, can you tell us what the likelihood will be that the first call we make tomorrow will be to someone in McGovern’s target population? We are really under pressure!” What is the likelihood that this will happen? How would you explain to the staffer your method for coming to that conclusion?