Vote functions are important devices for providing a ‘big picture’ of developments in electoral politics. However, the limited degrees of freedom upon which they are typically based mean that vote functions are rarely able to properly discriminate between competing accounts of electoral outcomes. They also fail adequately to capture the impact of ‘events’ or to recognise the extent to which the context of electoral competition can vary over time. Popularity functions that restrict themselves to relatively limited periods of time are capable of addressing all of these concerns: they enjoy more degrees of freedom, can take full account of the impact of ‘events’, and can focus on very specific electoral periods. Interestingly, however, Lewis-Beck’s vote function for post-war British politics contains variables that are very similar to those in a popularity function that was developed for the most recent (2001) British general election. In the British context, vote and popularity functions seem to provide quite similar accounts of the main drivers of party support. The advantage of both approaches is that they provide clearly specified, unambiguous—and falsifiable—accounts of the phenomenon under investigation.