The "blue wall" is the inverse of the "
red wall", a term coined in August 2019 to describe a set of constituencies in
northern England, the
Midlands and
Wales that had long been held by Labour, and many of which were later gained by the Conservatives at the 2019 election.
YouGov defines the blue wall as seats which are "currently held by the Conservatives; voted to Remain in 2016; and have a higher-than-average concentration of degree holders in the population (25%+)." The term saw significant use following the
2021 Chesham and Amersham by-election, in which the Liberal Democrats overturned a large Conservative majority;
Ed Davey, the
Leader of the Liberal Democrats, knocked down a literal blue wall of bricks with an orange mallet to symbolise his party's victory. He said afterwards that he believed "the blue wall in the south can be taken by the Liberal Democrats in large numbers of constituencies." In July 2021, Davey started the process of selecting parliamentary candidates in blue wall seats and the party revealed its first candidate, for
Guildford, the following month. Starting in December 2021, with the
2021 North Shropshire by-election, the usage of this term has evolved to mean any seat which the Conservative Party has traditionally held. The evolved usage has been demonstrated by Davey describing the North Shropshire seat as being another seat falling from the blue wall. In February 2022, think tank
Onward posited that the north of England—as part of the red wall—would be "the principal battleground in the next general election" with there being "no evidence of a southern 'blue wall' ready to fall". The study found that only 20% of battleground seats at the next election would be in southern England, and in such seats the Conservatives could "gain ground". Onward's director Will Tanner said, "While the south is steadily becoming less Conservative over time, there is no blue wall waiting to fall across the
Home Counties in two years' time". However, Onward did admit that certain seats "in London and the south-east are drifting away from the Tories and could fall in two or three elections' time", with data analyst James Blagden observing that "[t]he heart of the Tory party has been shifting northwards for the last 30 years" yet any potential of their "traditional southern heartlands slowly drifting away" existed in the long-term, with their "greatest short-term concern" being "backsliding in the red wall, losing their iconic 2019 gains, and putting their majority at serious risk." A few weeks after the
2023 local elections, which saw the Conservatives lose over 1,000 seats, former Conservative minister
David Gauke told
The Observer that he believed the blue wall "is going to crumble", but not for some time. "The Conservative party’s got a real long-term problem in the home counties," he said. "
Rishi Sunak is perfectly capable of appealing to blue wall seats, but he's the leader of a party that people have seen over quite a long period of time heading in a particular direction. Those memories are not going to disappear quickly. There's an element of 'long
Boris' about it all."
Politics.co.uk has indicated "42 Blue Wells" that are vulnerable for Labour in the
2024 general election. Campaigning in the
2024 local elections,
Ed Davey said he was confident of toppling the "Tory Blue Wall in Surrey". ==Blue wall constituencies==