Could tactical voting force Rishi Sunak out of No 10?

The three upcoming crunch by-elections all have the potential to swing votes decisively for the main parties contesting them, writes John Curtice

Labour would be expected to win Uxbridge in a general election if it were on course to win an overall majority (PA Archive)

Three by-elections occasioned by the sudden decisions of Boris Johnson and two of his acolytes to leave the House of Commons. None of them are contests that Rishi Sunak will relish, at a time when his party is still as much as 16 points behind Labour in the national polls. Yet they are, nevertheless, three by-elections with a rather different character.

Mr Johnson’s Uxbridge seat on the western periphery of London looks by far the most difficult of the three seats for the Conservatives. True, a recent poll conducted by Lord Ashcroft suggested Mr Johnson would have won the seat if he had fought the by-election following a successful recall petition. In the event, Mr Johnson has decided not to follow that path.

Labour only need a 7.5 per cent point swing, little more than half the 14 per cent figure currently being registered in the national polls. It is also well below the near 12 per cent swing Labour recorded in the three by-elections that have been held (all in Labour seats) since Sunak became prime minister.