This article examines the causes of stability and change in vote intentions during the 2014 Belgian federal election campaign. Drawing on data from the 2014 Parti Rep Belgian Voter Survey, our study aims to explain why a large number of voters have switched their vote intention in the weeks preceding the federal elections. To this end, we test a series of hypotheses drawn from different theories often referred to in the literature to account for campaign volatility. The results of our analysis reveal that voters can decide to change their vote preferences during the campaign due to strategic considerations related to their perceptions of the coalition potentials of parties. We also find that voters with a low level of political interest are more likely than highly interested voters to switch from one party to another in the weeks preceding the electoral contest. Unsurprisingly, a high degree of affection for the favourite party proves to be a barrier against campaign volatility. The higher the level of affect directed to the most preferred party, the more stable will be the vote intention. Moreover, results show that citizens with a low level of external political efficacy are more prone than others to switch parties in the last weeks of the campaign. By contrast, the ideological profile of the voter has no significant impact on campaign volatility.