Election Matters: Do General Election campaigns actually influence the result?

ITV News election analyst Professor Jane Green looks at why political campaigns rarely influence voters, and what actually helps people make up their minds

Do election campaigns matter? Do they determine the outcome?

They must - surely?

Well, no. Campaigns rarely have a big effect on the outcome.

During an election campaign, some people might be deciding how to vote, but often the winning party remains the same as would have won had the vote taken place on the very first day of the campaign.

This graph shows polling in the weeks of the 2015 election campaign period. From the start of the campaign to the end, almost nothing changed.

That’s quite extraordinary when you think of all the hours spent campaigning and all the money spent by parties on election campaigns.

Why do campaigns have little bearing on the outcome?

Elections are much more about the fundamentals; the long-term things that mattered before the campaigns began. We can think of the things that have moved the polls since 2019. Can a campaign really undo those reputational crises for the Conservatives this time around?

What are voters driven by?

In addition to the big political events that shape vote choice before campaigns, as voters we also have deeper drivers than simply what we see happening in an election campaign.

We are complex individuals, shaped by our upbringing; those who influenced us when we were first finding out about politics, and our deeper values and beliefs. This means we can see campaigns as just a small part - a blip really - in a much longer sequence of influences on how we vote.

The first things that influence us are the political and social identities, and the political values we come to hold when we are entering adulthood.

Does someone see themselves as working class, as the kind of person who votes Conservative, or who wants to see the state do more to help the poorest in society?

Those identities inform our attitudes - how we view policies or ideology.

In turn, those attitudes inform our evaluations. Then, and perhaps only then, we look at leaders, how the economy is doing, and other issues. But all along, that is shaped by those fundamental identities, values and beliefs.

Have you heard our podcast Talking Politics? Every week Tom, Robert and Anushka dig into the biggest issues dominating the political agenda…

Out of all that comes our vote choice. So the campaign is a very small part of what drives our voting. Unless someone remains undecided, and then it is a useful time people take a bit of notice. But it would be extraordinary if a campaign shaped those things we’ve lived with our adult lives.

Do campaigns sometimes matter?

Do campaigns sometimes matter? They can, if they tell us something important and different to what people thought beforehand.

Consider the 2017 election race - lead by Theresa May for the Conservatives and Jeremy Corbyn for Labour.

In this graph we can see that Conservative support dropped, and Labour support improved. Theresa May’s campaign was seen as pretty disastrous, whereas Jeremy Corbyn performed better than expectations.

That mattered because Labour needed to win back undecided voters, who were yet to make up their minds about their new leader, Jeremy Corbyn.

We can see the flow of Labour voters to undecided between the 2015 election and the month before the campaign, using British Election Study data. But then the campaign succeeded in winning most of these undecided voters back, as well as convincing some Conservatives.

In the current election, the Conservatives need to pull off the very same trick, but remember it isn’t a given this will happen. The 2017 result was a rare campaign change, and it only happened because Labour out-performed expectations and the Conservatives under-performed expectations. 

If Rishi Sunak fights a campaign like Theresa May did, Labour could see their position improve. 

So do campaigns matter?

So, do election campaigns matter? Very rarely. They matter for informing us about our vote, and they can sometimes be influential, but they are very rarely decisive on the outcome of an election.

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