How Much Each Party Spends to Buy Your Vote in UK Elections


I’m not a hugely political person, and being a swing voter, tend not to have a political axe to grind, but recently I saw an infographic from the FT on Twitter that gave an interesting breakdown of donations to political parties.

We, in the office, wondered what the numbers would look like when normalised in some way to make them comparable.

So after collecting donations data from the Electoral Commission and party voting data for the last two elections from Wikipedia (2005 and 2010), I found some interesting things. Firstly from a very high level :-

Election Donation Value (£K) Votes Cast £ Donations Spent / Vote Votes / £K
5 May 2005 £130,760 27,135,415 £4.82 208
6 May 2010 £274,134 29,520,569 £9.29 108
7 May 2015 £246,805*      

[edited 06May15] *Donations up to 5th May 2015

Elections are becoming more expensive to run and so the value of donations per person is rising, having roughly doubled between the 2005 and the 2010 election. The 2015 election looks like being of a similar magnitude to 2010.

The analysis of ‘£ donated / Vote’ by party shows a couple of interesting things. I’m calling this ‘Election Spend Cost’ for the purpose of this article.

Election cost 1

Election cost 2

A few observations that the data tells us …

  • The BNP’s Election Spend Cost is very low compared to any other party. I would suggest that their supporters don’t need to be swayed by expensive electioneering.
  • Both BNP and UKIP’s Election Spend Cost is decreasing, despite the average £ / vote almost doubling in the same period. These parties sit at a similar end of the political spectrum and this could indicate between the two elections, a general movement toward nationalistic parties.
  • However when looking at the SNP and Plaid Cymru, these show an interesting difference. The Party of Wales spends as much as the Conservative Party to gain votes, yet the SNP is almost half. Superficially that would suggest that SNP have a much greater engagement with their voters than Plaid Cymru.
  • Of the three major parties, the Lib Dems have a significantly lower Election Spend Cost than either of Labour or Conservatives.

Further to this, I analysed the ‘£ spent / seat contested’, with some interesting results.

election cost 3

election cost 4

Drawing further observations …

  • UKIP has spent the same amount per seat contested in both elections
  • The Torys almost trebled their spending per seat, massively increasing their spending as compared with any other party.
  • The BNP spends very little in each contested seat.

Obviously there are other larger factors that affect election outcomes, such as policies, current economics, who the current incumbent is, plus any major election blunders … but perhaps the data suggests that the simpler and more straight forward a party’s message, the cheaper the marketing message to attract votes. The more complex and nuanced the policies and message of a party, the higher the Election Spend Cost.

I wonder if there is the basis of a predictive model for election outcomes?

[Edit 12May2015] See here for my predictions based on election spend!

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