Will leader satisfaction among party supporters predict GE2017?

One of my earlier posts showed how well Ipsos MORI leader satisfaction ratings among supporters of the two main political parties predicted UK general election outcomes since 1997. Ipsos MORI Political Monitor for June 2017 showed that Theresa May had 81% approval among Conservative party supporters, and Jeremy Corbyn had 71% approval among Labour party supporters. So, despite the narrowing of the ‘voting intention’ polls, I am still predicting a Conservative majority. Of course, those satisfaction ratings could still change…

Party leader satisfaction among supporters of the two main parties accurately predicts election outcomes since 1997 (see this post for discussion of the 2010 coalition outcome)

Update: And the size of that majority? I’ve no evidence of that. My feeling is about 50 seats. As a Political Studies Association member I was invited to complete the PSA ‘expert predictions’ survey in mid-May (when the Conservatives were doing very well in the polls). At that time I gave the Tories a 20 % chance of a 100+ majority and a 1% chance of a 150+ majority – that put me in the lowest decile of the expert predictions! So, we’ll see.

Here is the table from that survey (which was taken before the recent Labour surge in the polls).

Table from PSA expert survey 2017 (online survey 16-26 May)

Post-election update: Well, along with most other predictions (but not all) I was quite wrong about the Conservatives increasing their majority! Instead, they lost seats and Labour gained substantially, though the Conservatives remain the largest party.  The final seat counts are Cons 318, Labour 262, SNP 35, Lib Dem 12, DUP 10, Sinn Fein 7, Plaid Cymru 4, Green 1, Other 1. So Theresa May hangs on with the help of the Democratic Unionist Party.

The leader satisfaction ratings, however, did predict that Conservatives would end up ahead of Labour. I still think these ratings are a good measure of voter intent, despite the fact that they don’t predict the size of the lead, nor (as I failed to notice) do they predict that the leading party will have an overall majority. For what it’s worth, I was among the 10% of PSA survey-takers who correctly surmised that the chance of a large Tory majority was low.

Who’s Satisfied?

In a previous post (also published on the LSE British politics and policy blog) I showed that satisfaction with the leaders of the two main parties was a good predictor of electoral outcomes over the past 9 UK general elections. That measure, however, combines responses from people who support the party and those who don’t. So in this post I’m exploring leader satisfaction among party supporters as a way of measuring the level of ‘enthusiastic support.’ Continue reading