Talking to the Converted or Reaching Out to the Uncommitted? Who Do Political Campaigns Influence?

Research on campaign effects in British elections has repeatedly shown the importance of constituency campaigning. Other things being equal, the more parties campaign locally, the more votes they gain and the fewer votes go to their rivals. However, implicit in the literature is the assumption that campaigns affect all voters in the same way. There are good theoretical reasons for doubting this. For instance, we might expect that strong partisans will be less likely to change their vote decisions consequent to exposure to a party's campaign than weaker partisans and nonaligned voters. Similarly, political campaigns are likely to have a larger impact on those relatively uninterested in politics than on the more interested, since the former may need the extra information and stimulus offered by the campaign to make up their minds. The paper employs campaign panel data from the 2005 British Election Study to evaluate these and other claims. Who is most, and who is least, open to influence by parties' campaign efforts?.