By-Election Loss Comes As Major Shock To Governing Conservatives

The UK's governing centre-right Conservative Party has suffered one of its most notable by-election shocks in living memory, losing the previously rock-solid seat of Chesham and Amersham to the centrist Liberal Democrats. The Liberal Democrats overturned a Conservative majority of over 16k, in the end winning by the comfortable margin of 8,028 votes.

Chart 1. Conservative and Liberal Democrat Vote Shares in Chesham and Amersham in 21st Century, %

Source: Electoral Calculus, BBC, MNI

• The seat, in the wealthy southern English county of Buckinghamshire, was Conservative since its creation in the 1970s and is archetypal of the 'Home Counties Conservative' seat, with an affluent, well-educated, property-owning population, that voted strongly to remain as part of the EU in the 2016 referendum, with a high proportion of individuals that work for London-based companies.
• It should be noted that by-elections in the UK are often viewed by voters as an opportunity to vent frustrations at the gov't of the day, or the party that has controlled the seat most recently. In this case they were one and the same. There has been a significant local backlash against the HS2 high speed rail line from London to Birmingham that is set to run through the constituency, and proposed reforms to planning laws that would allow for the building of more houses on previously protected 'greenbelt' land has caused uproar in the pastoral constituency.
• Nevertheless, coming on the back of relatively poor results for the Conservatives in southern England in May's council elections, there will be growing concerns among southern English Conservative MPs that reforms to planning laws (always controversial in the Home Counties) and PM Boris Johnson's focus on winning and retaining constituencies in northern England combined with his more bombastic patriotic/nationalist rhetoric (depending on the individuals' opinion) is turning off middle-class socially liberal voters.
• The by-election result will not only be viewed as concerning for the Conservatives, but for the centre-left Labour party too. Labour won just 622 votes, 1.6% of the total, marking the party's worst-ever by-election result. Should Labour lose the upcoming Batley and Spen by-election on July 1 to the Conservatives it would put party leader Sir Keir Starmer in a difficult position of not being able to retain Labour heartland seats in the north from Johnson's Conservatives, but also unable to offer a significant challenge in historically Conservative areas in the south (a key factor in Tony Blair's 1997 landslide win for Labour).