We consider the problem of poll manipulation in political elections. In the context of strategic voting, we are interested in whether a polling institute can manipulate the information it communicates to voters in order to influence the outcome of the election. We start with a version of the problem where the polling institute is allowed to send any score to voters. Then, for realistic reasons, we investigate a restricted version in which the polling institute cannot announce scores which are too far from the truthful ones. While we show that both decision problems are computationally hard, we go beyond this worst-case complexity analysis by using probabilistic tools to address the possibility of successful and efficient manipulation in practice, w.r.t. several natural preference distributions.