Will tactical voting mean defeat for the Conservatives at the next general election?

The Conservative Party is suffering another bout of jitters after two crushing by-election defeats in Tiverton and Honiton and Wakefield. The main reason Tory MPs are fretting is that the tactical voting by Labour, Liberal Democrat and Green supporters in both seats makes it hard to dismiss the results as a typical outbreak of midterm blues.

True, parties often bounce back to win a general election after by-election setbacks, when voters have a free hit and know they are not choosing a government. But Thursday’s results have focused Tory minds on the 1997 general election when anti-Tory tactical voting contributed to Tony Blair’s landslide. He and Paddy Ashdown, the Lib Dem leader, became convinced their parties needed to cooperate to end what Roy Jenkins called a century of Tory domination.

They agreed a below-the-radar non-aggression pact in which they soft-pedalled in constituencies where the other party stood a chance of ousting the Tories. Academics calculate that it delivered 30 seats. Although Blair would have won without it, he would not have got the 179 majority that took the Tories 13 years to wipe out.

Ominously for the Tories, Keir Starmer and Ed Davey have quietly struck a similar deal. They are not close in the way Blair and Ashdown were but, due to Labour’s disastrous defeat in 2019, recognise they need to do business to have a chance of ending Tory hegemony in 2024. They deny even an informal pact; admitting one could frighten off soft Tory voters who do not want a Labour government and amplify Tory warnings about a post-election “coalition of chaos”.

There are few seats where Labour and the Lib Dems go head-to-head, so it makes sense to target their resources to maximise the chances of a Tory defeat. The good news for them is that voters are doing it by themselves; Sir Keir and Sir Ed judge such DIY tactical voting a more effective weapon than a formal progressive alliance in which they would stand down in some seats (which in any case would be hard to impose on their parties). But Compass, the pressure group, argues that the electoral mountain is bigger than in 1997 and so more formal cooperation is needed. Neal Lawson, its director, told me: “The people are way ahead of party leaders, voting and campaigning on an industrial scale. It worked in these by-elections but needs leadership to be replicated in a general election.”

Now that tactical voting is becoming entrenched again, many Tory MPs fear for their seats, making it more likely they or the cabinet will oust Boris Johnson. A new leader would almost certainly boost their chances of retaining power. After the Tories dumped Margaret Thatcher in 1990 and installed John Major, voters judged they had already had a change of government and gave the Tories a fourth term. That will worry Labour today.

However, by 2024 the Tories will have been in power for 14 years. “Time for change” is a powerful political slogan, often competing with “don’t let the other lot ruin it”. Widespread tactical voting will be needed to achieve such a change. Worryingly for the Tories, there are growing signs it will happen.