Could tactical voting oust the Conservatives at the next general election?

The potential flaw is that voters are not a bloc that can be moved from one column to another, writes Andrew Grice

It seems unlikely that there will be any formal pact between Labour and the Lib Dems (Getty/PA)

Some Conservatives argued that the North Shropshire by-election was a bad result for Labour because the Liberal Democrats overtook the party from third place in 2019 to win the seat. Yet some senior Labour figures believe it was a very good result for them.

For years, there has been talk of an anti-Tory progressive alliance involving Labour, the Lib Dems and the Greens. Some local pacts, under which candidates stood aside for the party with the best chance of winning, were agreed at the 2017 election, but the Greens got their fingers burnt when other parties did not reciprocate.

The potential flaw is that voters are not a bloc that can be moved from one column to another. Some “soft” Tory voters might lend their support to the Lib Dems, but not to Labour. But voters now seem to be doing it by themselves, in a DIY democracy made necessary by the first-past-the-post system. The Labour vote collapsed in Chesham and Amersham, as well as in North Shropshire, to help the Lib Dems claim famous victories. In a variation on the theme, the Lib Dems campaigned hard in a few areas in Batley and Spen where Tory support was soft, helping Labour over the line.