  Social networks are increasingly being used to conduct polls. We introduce a
simple model of such social polling. We suppose agents vote sequentially, but
the order in which agents choose to vote is not necessarily fixed. We also
suppose that an agent's vote is influenced by the votes of their friends who
have already voted. Despite its simplicity, this model provides useful insights
into a number of areas including social polling, sequential voting, and
manipulation. We prove that the number of candidates and the network structure
affect the computational complexity of computing which candidate necessarily or
possibly can win in such a social poll. For social networks with bounded
treewidth and a bounded number of candidates, we provide polynomial algorithms
for both problems. In other cases, we prove that computing which candidates
necessarily or possibly win are computationally intractable.
