The MEP elections in Great Britain, to be next held on 23 May 2019, use the d'Hondt system for allocating seats in each of eleven constituencies/regions.
Whether the Remain parties (Lib Dem, Green and Change UK) have shot themselves in the foot (feet?) by competing over the same small pool of voters is an interesting question.
Let's treat this as an unofficial In-Out Referendum and assume votes cast are in line with current opinion polls and are the same in each constituency, as follows:
Leave
Brexit Party - 31%
UKIP - 4%
Remain
Lib Dem - 10%
Green Party - 10%
Change UK - 10%
Undecided - neutral - ambivalent
Labour - 22%
Tories - 13%
The more seats there are in a constituency, the closer the result is to proportional representation; the fewer seats, the closer the results are to FPTP.
If you crunch the numbers (or use Paul Lockett's fine calculator) for the largest constituency with ten seats (South East), the end result is the same whether the Remain parties had put up a single list or not - Leave 4 seats, Remain 3 seats and Undecided 3 seats.
The difference is that with a single list and 30% of the vote, Remain would win seats 2, 5 and 9; with three competing Remain parties, they will win seats 7, 8 and 9. So they will do relatively worse in smaller constituencies and relatively worse overall.
The reverse is true for Leave, only not as markedly. If Remain had put up a single list, Leave would win seats 1, 4, 8 and 10 of a ten-seat constituency. With the Remain vote split, they will win seats 1, 3, 5 and 10.
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To sum up, for various sizes of constituency with a split Remain vote, seats will be as follows:
3 seats = Leave 2, Undecided 1
4 seats = leave 2, Undecided 2
5 seats = Leave 3, Undecided 2
6 seats = Leave 3, Undecided 3
7 seats = Leave 3, Undecided 3, Remain 1
8 seats = Leave 3, Undecided 3, Remain 2
9 sweats = Leave 3, Undecided 3, Remain 3
10 seats = Leave 4, Undecided 3, Remain 3
As only five constituencies have seven or more seats, Remain have definitely messed up badly. With a single list Remain vote, seats would be as follows:
3 seats = Leave 1, Undecided 1, Remain 1
4 seats = leave 2, Undecided 1, Remain 1
5 seats = Leave 2, Undecided 1, Remain 2
6 seats = Leave 2, Undecided 2, Remain 2
7 seats = Leave 2, Undecided 3, Remain 2
8 seats = Leave 3, Undecided 3, Remain 2
9 sweats = Leave 3, Undecided 3, Remain 3
10 seats = Leave 4, Undecided 3, Remain 3
Just sayin'...
Debate Magazine
