Why are electoral campaigns different across the globe? Canvassing varies dramatically across countries. In most countries citizens never meet candidates, certainly not at their doorstep. In others, however, voters often find themselves opening the door to would-be MPs. How do we explain what voters experience during a campaign? Is it simply down to a country’s traditions or is it shaped by electoral institutions? Why do candidates seem to work harder in some countries and less so in others? Should they not all be motivated by the same goal?

In an article recently published in the British Journal of Political Science, we explore whether and how electoral institutions affect the way candidates act during first-order electoral campaigns. If system-level differences are indubitably playing a role in shaping voters’ experience of a campaign, we lack evidence of whether the design of electoral systems also plays a role. To fill this gap, we disentangle the extent to which candidates’ individual-level campaign efforts vary under different electoral set ups.

We use data from the cross-national Comparative Candidates Study to explore whether electoral institutions shape the nature of campaigns – their intensity and focus. In doing so, we assess candidates’ campaign behaviour in fifteen countries against the electoral set up as well as several individual-level characteristics (incumbency, likelihood of success, career stage, etc.) and country-level differences. Our results show that electoral institutions are indeed a key predictor of candidates’ campaign strategy with regards to both its intensity and focus.

Electoral institutions are classified here by i) plurality versus proportional dichotomy, ii) an electoral incentives index based on the work by David Farrell and Roger Scully (2007), and iii) district magnitude.

Campaign effort is more intense and complex in candidate-centred systems

First, we evaluate the intensity and complexity of candidates’ overall campaign efforts in the run up to first-order parliamentary elections. With regards to campaign intensity, we conceive and measure it in terms of time spent campaigning in the last month leading up to the election. With regards to campaign complexity, we build an index that describes how many activities a candidate used in her campaign. Namely, we explore the extent to which candidates make use of canvassing, direct mail, online campaigning, newspaper interviews, and TV interviews.

It becomes clear that, even when controlling for various individual-level characteristics and country-level differences, electoral institutions systematically influence campaign effort. We find that under candidate-centred electoral institutions – for example, single-member district (SMD) plurality, open-list proportional representation (PR) and single transferable vote PR (PR-STV) systems – candidates’ campaign efforts tend to be more intense and complex than under party-centred mechanisms such as closed-list PR. For example, we find that candidates in plurality systems are predicted to spend 11 hours more per week on campaigning than their counterparts in closed-list PR. Moreover, the likelihood of candidates using all five campaign tools is considerably higher in candidate-centred systems than party-centred ones (89% versus 1%). Campaign effort is substantially more intense and complex in candidate-centred systems. This finding, while intrinsically intuitive, contradicts previous insights from studies of candidates running for office to the European Parliament.

District magnitude also influences campaign intensity and complexity. The smaller the constituency, the more intense and complex campaign effort tends to be. These effects are, however, of a smaller scale. For example, a shift from the smallest to largest district brings about a 9% decline in candidates’ likelihood of conducting a high complexity campaign (from 24% to 15%).

Candidates tailor their campaign message to the electoral context

We also shed light on the relationship between individual candidates and their parties by assessing how electoral institutions influence candidates’ campaign focus. We do so by using a survey question that directly addresses the primary aim of one’s campaign, asking whether the candidate tried to attract as much attention as possible to her party (0 on a scale from 0 to 10) or herself (10). This offers a unique comparative insight into the kind of messages that candidates convey to the electorate through their campaigns.

Not surprisingly, we find that the extent to which candidates’ campaign messages focus on themselves versus their party is also influenced by the structure of the electoral set up. Candidate-centred electoral systems incentivise candidates to opt for a more candidate-focused campaign strategy, while party-centred systems push candidates to place emphasis on the party rather than themselves. The predicted score for the measure is 2.2 points higher for candidates in plurality systems than those in proportional ones (5.1 versus 2.9), holding everything else constant. The same pattern is detected when using the electoral incentives index. While the debate on the personalisation of electoral campaigns has, to date, focused mostly on party leaders, our findings indicate that it should feature the candidate side more prominently.

What does it mean for electoral system design?

It is generally accepted that electoral campaigns are shaped by various candidate- and party-specific characteristics as well as dynamics unique to the country in question. The empirical evidence uncovered here adds electoral institutions to the list. It suggests that the consequences of electoral design go beyond influencing proportionality, the number of effective parties, and the representation of minorities and women.

The amount and type of campaign stimuli that voters tend to experience in the run up to the polling day is shaped by electoral institutions. Simply put, candidates’ campaign efforts tend to be more intense, complex, as well as candidate-focused under candidate-centred electoral institutions than party-centred ones. This should be taken into account when designing and choosing an electoral system.