Will general election turnout stop UKIP repeating their performance?

UKIP's record breaking performance has the world (or that subset of it that follows English local elections closely) talking about whether they might repeat this performance at the general election. If they did, then they might replace the Liberal Democrats as the third party in the House of Commons.

Before getting carried away with speculation on Nigel Farage's role in a future coalition government, it is worth considering some factors that might limit this. One factor is the odd electorate that votes in local elections. While the BBC's projected national share accounts for the difference in the areas that vote, it doesn't account for the difference in the electorate that turns out. These differences can be large, just 31% of eligible voters made it to polling stations yesterday compared to the 65% who voted on election day.

These differences aren't random either. In particular, local elections voters are much older  those at general elections (broadly, the elderly will turnout in every election whereas the young tend to only show up for high profile contests). Conservatives and liberal democrats have been the traditional beneficiaries of this differential turnout but UKIP has a strong base of support among the elderly.

So what would these results have looked like if the turnout had been 65% rather than 31%. To give a rough answer to this question I looked at how much share UKIP gained since 2005 (a general election) in each ward depending on how turnout changed between the 2005 General Election and 2013's local contests.

	UKIP vote change 05-13
Turnout change 05-13	-0.065
	(2.42)*
_cons	17.810
	(15.14)**
R2	0.03
N	163

* p<0.05; ** p<0.01

As expected, UKIP improved their performance more in contests that saw a sharper drop in midterm turnout. However, this would not have been sufficient to dent their performance greatly: they would lose a total of 2 percentage points bringing them from a 23 point PNS to a 21 point result.

While UKIP benefited from low turnout, it is not enough to begin to explain their huge electoral gains. It will take more than robust turnout to reverse their success in these elections.


Note: These results are also robust to a set of controls:

	UKIP vote change 05-13
Turnout 05-13	-0.061
	(2.25)*
Population Density	-0.015
	(0.29)
% aged 65+	0.293
	(2.05)*
% white	-0.156
	(0.67)
% aged 18-24	-0.193
	(1.27)
_cons	28.916
	(1.31)
R2	0.10
N	160

* p<0.05; ** p<0.01

Caveats:

• See previous post
• I realise I'm in danger of contributing to the "questions to which the answer is no" genre of blog writing. In my defense I didn't know that the answer would definitely be no in advance.