Read more about methods of electoral research

Much like exit polls, opinion polls are surveys which ask members of the public certain questions relating to politics and elections. However, there are a number of key features which distinguish opinion polls from exit polls.

Opinion Polls vs Exit Polls

One key difference between exit polls and opinion polls is the timing. Exit polls are conducted after an election or referendum and survey how people actually did vote. Opinion polls are conducted before elections and survey how people intend to vote.

Moreover, opinion polls can ask a much broader range of questions to gauge the mood of the electorate. Examples of opinion poll questions include:

  • If the election were held today, who would you vote for?
  • Do you think the country is moving in the right or wrong direction?
  • Do you approve of the job the president is doing with regards to foreign policy?

Another key difference is who does the polling and for what purpose the results are used. Exit polls are typically undertaken by news networks in order to analyse and predict the results of elections directly after voting closes. Opinion polls, on the other hand, are undertaken for analytical and predictive purposes by news networks. They are also regularly used by political parties as a strategic campaigning tool.

Methods of polling

Opinion polls have historically been conducted over the phone or in person. However, technology has been progressing so rapidly that internet surveys are now very much in vogue. Throughout an election campaign, three broad types of polling are used:

  • Benchmark polls – taken at the beginning of a campaign, these polls give candidates an initial idea of their popularity within the electorate. If their popularity is very low, candidates will likely not even run for election.
  • Brushfire polls – these polls inform candidates of any progress being made during the campaign. They allow candidates to target specific demographics in which they may have slumped in order to improve performance in the election.
  • Tracking polls – these polls are repeated at regular intervals and survey the same group of people. They are designed to measure general shifts in opinion, rather than the level of popularity a candidate has.

Polling pitfalls

Whilst opinion polls are certainly helpful in providing insights into the mood of the electorate, their predictive power is limited to the quality of the sample group surveyed. How well does the sample reflect the diversity of the electorate as a whole? There is always a statistical ‘margin of error’ involved in conducting opinion polls.

One of the most notable botched opinion polls in history predicted FDR to comfortably lose the 1936 US presidential election. The non-scientific straw poll used by the Literary Digest predicted Alf Landon would be the future president with 57% of the popular vote. In reality, FDR won with a sizeable 63% of the vote.

Just because we now live in the 21st century, doesn’t mean we’ve eschewed polling pitfalls altogether. A classic illustrative case is the 2015 UK general election. The vast majority of opinion polls indicated that neither of the major parties, Conservative nor Labour, would be able to form a government in their own right. Instead, they predicted another UK coalition government made up of either the Conservatives or Labour and one or more minor parties. The actual result saw the Conservative Party elevated into government by a majority of 12 seats. The lesson? Be aware of polling pitfalls!