They aren’t mini-general elections, and don’t predict next year’s result
On Friday morning, the media will be full of commentators concluding that the Conservative Party is doomed to lose the next election because of the by-election results. Or, alternatively, it will be full of people concluding that the Conservatives stand a chance of victory after all. Do not pay either any attention.
The by-election results will tell us a lot about what the voters in Uxbridge, Selby and Somerton think of the Government. Where it is set to be less useful is in revealing the national political mood.
If the swing in those three constituencies is similar to the swing in the national opinion polls, then it will tell us practically nothing we didn’t already know. If that isn’t the result, then that still doesn’t tell us much new about wider public opinion either, because by-elections are very strange beasts.
To be clear, they are not mini-general elections. Normally a major factor in how people vote at general elections is the fact they are picking a government and a prime minister. The voters this Thursday know that whoever they vote for, and whoever wins, they’ll still have a Tory government the next morning. That provides an opportunity for a protest vote, or to pay more attention than usual to the local candidate.
Voters in the seats being contested on Thursday will have been besieged by prospective candidates and accompanying leaflets, telling them which party is best placed to kick out the Government, which is one of the reasons why the Liberal Democrats often overperform in by-elections.
Meanwhile, there’s no guarantee that these seats bear any similarity to the country as a whole. If the Conservatives do better in, for example, Uxbridge, it could be due to specific local issues that don’t matter elsewhere. This is by no means unlikely — the Uxbridge campaign has been dominated by London Mayor Sadiq Khan’s Ulez scheme, due to be expanded to cover the constituency next month. A smaller swing there may imply something about support for that particular issue, but will divulge little about the country away from outer London.
Yet just because the by-election results don’t tell us much about the national political mood, it doesn’t mean they aren’t still important. Their significance simply stems more from their impact. If the Conservatives lose all three votes, it will further entrench the perception of a party doomed to defeat, while further demoralising Tory MPs. It would also make Sir Keir Starmer look more like a leader on the path to victory. If the Conservatives manage to save those seats, suddenly the media narrative will switch to stories about Rishi Sunak turning it around, about how they may just win after all.
All those articles on Friday morning might tell you a great deal about the political narrative as we head into the summer. But broader public opinion? Not so much.