The Conservatives victory in the Hartlepool by-election means the Brexit realignment of British politics is still taking place … or does it? In fact, Labour’s defeat in Hartlepool for the first time in over 60 years should be put down to tactical voting rather than Brexit realignment, at least for now. It will be the two upcoming by-elections in Batley & Spen on 1st July representing the Red Wall and Chesham & Amersham on 17th June 2021 representing the Blue Sea that will answer the question “Is Brexit realignment is still continuing or did it end in December 2019?”
The results are in and it is now time to review my predictions of the Copeland and Stoke-on-Trent Central by-elections. How well did my by-election model do and what lessons can be learnt? Let’s look at the numbers first.
Originally posted on 19th February 2017. I then added an updated forecast on 22nd February which can be seen at the bottom of this post.
If UKIP want to supplant Labour in the North England, they must win Stoke-on-Trent Central to kickstart this trend and the odds are 2 to 1 that they will win. That is my forecast after running my by-election model on Stoke-on-Trent Central. For more details about the methodology, please read my description of how I forecast by-elections in the Brexit era.
My model uses both the breakdown of the 2015 General Election results when Labour held the seat with a 16% majority on a 50% turnout (the 2nd lowest turnout in the whole of the UK in 2015) and the 2016 EU referendum result where I estimate that Leave won with 71% of the vote on a 60% turnout. This makes this seat the 17th most Leave seat in the UK and it is worth noting that its two neighbours were #22 (Stoke South) & #3 (Stoke North). In % terms, the increase in number of voters in 2016 was the 22nd highest in the UK and has created a substantial Non-GE segment of 17% of 2016 voters that have the potential to influence the by-election. Whether these non-voters from 2015 will vote in the by-election is one of the big uncertainties and it will be fascinating to see if they do.
Since the UK voted to leave the EU on 23rd June 2016, there have been 3 contested parliamentary by-elections (Witney, Richmond Park, Sleaford & North Hykeham) and one uncontested by-election (Batley & Spen which was the late Jo Cox’s seat). Many commentators have analysed these results to see how the referendum result has impacted on parliamentary voting intentions. Whatever voter dynamics are revealed, it is reasonable to assume that they are likely to influence future by-elections. In late October 2016 just after the Witney result, I realised it could be possible to build a by-election model by combining two sources of data.
- My own estimates of the Leave & Remain votes in each of the 650 parliamentary constituencies where I calculated that 400 out of 650 seats voted Leave.
- My interpretation of the Lord Ashcroft “exit poll” carried out on 21st to 23rd June 2016 and published immediately after the results were announced.
At the time, I described my by-election modelling approach in a youtube clip and that is worth listening to. I have made some changes to my model since then so this post is the most up to date version of my model. I will illustrate the basic principle using the Witney by-election (David Cameron’s former seat) of 20th October 2016 where the top line numbers are: