Here is a table of English Labour constituencies in which the Brexit Party won more than 10 per cent of the vote in the 2019 general election…

…and its vote was bigger than the majority.

Barnsley Central: 11,223 votes   3,571 majority   30 per cent 2nd

Barnsley East: 11,112   3,217   29 2nd

Blaydon: 5,833   5,331   13

Chesterfield: 4,771   1,451   10

Doncaster Central: 6,842   2,278   17

Doncaster North: 8,294   2,370   20

Easington: 6,744   6,581   20

Hemsworth: 5,930   1,180   14

Houghton and Sunderland South: 6,115   3,115   16

Jarrow: 4,122   7,120   10

Kingston Upon Hull East: 5,764   1,239   18

Kingston Upon Hull West and Hessle: 5,683   2,856

Makerfield: 5,817   4,740   13

Normanton, Pontefract and Castleford: 8,032   1,276   17

Rotherham: 6,125   3,121   17

Sheffield South East: 4,478   4,289   11

Stockton North: 3,907   1,027   10

Sunderland Central: 5,047   2,964   12

Washington and Sunderland West: 5,439   3,723   15

Wentworth and Deane: 7,019   2,165   17

  • The seats marked in blue are ones in which if the Brexit Party vote is divided in half, that half is greater than the majority.  They are this column’s eleven Tory targets (assuming present boundaries).
  • There are constituencies in which the Brexit Party vote was more than ten per cent, but in which its vote was smaller than the majority: North Durham, North Tyneside, Sheffield Brightside & Hillsborough, South Shields, St Helens North, St Helens South & Whiston, and Wigan.  These aren’t listed above.
  • Ten per cent is an arbitrary figure: we might gone up to 15 per cent or down to five: but one has to start somewhere.

  • In short, the assumption in the seats marked blue is that the Conservatives can gain at the next election more than half the vote won by the Brexit Party in the last one.
  • The key to these putative targets is the size of the Conservative vote in 2019.  The size of the majority in those seven seats named above, but not listed in the table, was boosted by a Tory number relatively low to the Labour number (at least, compared to those seats in the table).
  • To assume that the Tories scoop up only half of the 2019 Brexit Party vote in the table seats is arguably a conservative, small c, assumption.  Were two thirds assumed instead, then Hull West & Hessle, where the Conservatives would fall 18 votes were they to take half the 2019 Brexit Party vote next time, would fall into the blue column.
  • Brexit Party votes moving to the Conservatives would be extremely helpful to some Tory MPs in “Red Wall” seats – for example, to Nigel Fletcher in Don Valley, in which the Brexit Party won over 6000 votes and a 14 per cent share.
  • Every single one of the seats in the table is in the eastern half of England; Tory competitiveness is lower, and Labour more entrenched, in the western half – and the Merseyside constituencies named above: St Helens North, St Helens South & Whiston, and Wigan.
  • It may well, of course, be that all other things aren’t equal: for example, that the actual Tory vote falls next time – thus making this calculation useless.

In the Hartlepool by-election, the Conservative vote rose by 24 per cent, Labour’s vote fell by nine per cent: much of the blue rise will have come from the 10,000 or so 2019 Brexit Party voters.

But a precise estimate is impossible – not least because the turnout last week was 43 per cent, whereas in 2019 it was 58 per cent.  Our bedrock assumption, as above, is that at the next election the Tories can take at least half the 2019 Brexit Party vote.

Finally, we’re using South Yorkshire in a rough and ready sense.  The Hemsworth constituency, for example, is in the West Riding, as is the Normanton, Pontefract and Castleford, but the centre of gravity of these seats is in South Yorkshire.