Support our Nation today - please donate here

Tactical voting in the Senedd election: Who to back in the constituencies

26 Apr 2021 5 minute read
The 2016 Senedd election results (left) and the parties in second place in each seat (right)

Ifan Morgan Jones

In an ideal world, we should all vote in an election for the party that we think best represents us. And if you would rather stick to that ideal at the upcoming Senedd election on May 6 – go ahead!

However, despite an element of proportional representation, Senedd elections continue to depend primarily on the flawed First Past the Post system.

40 of the 60 Members of the Senedd are elected via constituencies through this ‘winner takes all’ method, and this means that a lot of parties have no realistic hope of victory in individual seats.

It also means that a large number of seats in the Senedd election are considered ‘safe’ – seats that, barring a massive upset, there is no real prospect of the dominant party losing.

Seats that I think could be considered quite ‘safe’ and would be big upsets if they changed hands include:

Aberavon, Alyn and Deeside, Arfon, Cardiff South and Penarth, Carmarthen East and Dinefwr, Carmarthen West and South Pembrokeshire, Ceredigion, Clwyd West, Cynon Valley, Dwyfor Meirionnydd, Islwyn, Merthyr Tydfil and Rhymney, Montgomeryshire, Newport East, Ogmore, Pontypridd, Swansea East, Swansea West, Torfaen, and Ynys Môn.

There’s probably no real point suggesting any tactical voting in these seats because it’s unlikely to make much difference to the result. Just vote for whoever you like.

Seats that could change hands but would be considered a ‘mild shock’ include:

Blaenau Gwent, Bridgend, Cardiff Central, Cardiff West, Cardiff North, Clwyd South, Monmouth, Neath, Newport West, and Preseli Pembrokeshire.

You may want to consider tactical voting here.

Seats that are genuinely competitive include:

Aberconwy, Brecon and Radnorshire, Caerphilly, Delyn, Gower, Llanelli, Rhondda, Vale of Clwyd, Vale of Glamorgan, and Wrexham.

People choosing to vote tactically could make a real difference here.

If you’re a Plaid Cymru voter

Plaid Cymru hold Rhondda and are in second place in Aberconwy, Blaenau Gwent, Caerphilly, Cardiff West and Llanelli, so obviously vote Plaid Cymru there if that’s who you want to win.

If your aim is to keep out the Conservatives at any cost you may want to vote Lib Dem in Brecon and Radnorshire, and Labour in Delyn, Gower, Vale of Clwyd, Vale of Glamorgan, and Wrexham.

You may also want to vote Labour in Bridgend, Cardiff North, Clwyd South, Monmouth and Preseli Pembrokeshire for the same reason, but these seats are less likely to flip.

Carmarthen West and South Pembrokeshire is probably safe for the Conservatives, and Plaid Cymru are a close third place behind Labour so you may want to stick with Plaid Cymru.

In Cardiff Central, if you care whether you’re represented by the Lib Dems or Labour it may be worth voting one or the other, but given the Lib Dems’ electoral doldrums, this seems less likely to flip.

If you’re a Labour voter

Labour are in the mix in almost every marginal seat so there’s less scope for tactical voting.

Aberconwy is a three-way marginal between Labour, Plaid Cymru and the Conservatives. But Labour have come 3rd here for three elections in a row so if you’re feeling generous it may be worth a Plaid Cymru or Conservative vote to help either over the top.

The only other genuinely competitive seat where Labour aren’t really in the mix is Brecon and Radnorshire – it may well be worth choosing between the Liberal Democrats and the Conservatives here.

If you’re a Conservative voter

There are a few seats where a tactical vote might be worthwhile for the Conservative voter, most of them Plaid Cymru / Labour marginals. Those are Cardiff West, Blaenau Gwent, Caerphilly, Llanelli, Rhondda, and Neath.

You may also want to choose between the Liberal Democrats and Labour in Cardiff Central.

If you’re a Liberal Democrat voter

The Liberal Democrats are only seriously competitive in four seats – Brecon and Radnorshire, which they hold, and Cardiff Central, Montgomeryshire and Ceredigion.

So it’s worth a tactical vote for Plaid Cymru, the Conservatives or Labour in Aberconwy.

It may also be worth choosing between Plaid Cymru and Labour in Cardiff West, Neath, Blaenau Gwent, Caerphilly, Llanelli and Rhondda.

And between Labour and the Conservatives in Bridgend, Clwyd South, Monmouth, Newport West, Preseli Pembrokeshire, Cardiff North, Delyn, Gower, Vale of Clwyd, Vale of Glamorgan, and Wrexham.


The above is dependent on 2016 results, the current direction of travel in polling, which seats flipped at the 2017 and 2019 General Elections, which seats the parties are actually targetting, and gut feeling.

A seat like Ceredigion, for instance, is quite marginal on paper based on the 2016 result but the Lib Dems lost the seat to Plaid in 2017 and fell into third place in 2019, and don’t seem to be putting as many resources into the campaign this time, so it could be considered relatively ‘safe’ for Plaid. But Ceredigion has thrown up unlikely results before.

And there are a lot of unknowns at this election, such as where the 2016 UKIP vote will go, a lot of disagreement in the polling about how well Labour and the Conservatives will do, a lot of political instability at Westminster, and also the existence of many smaller parties such as Propel, Gwlad, Reform UK and Abolish that didn’t exist or weren’t in the mix to the same extent in 2016.

In 2016, all the seats pundits thought were likely to flip didn’t, and one they didn’t think likely – Rhondda – did. So there may be some surprises.

The most likely constituency to be disrupted by a smaller party is Cardiff West where the 2016 Plaid Cymru candidate is now running a high-profile campaign for Propel. There is no precedent for this and what impact will have on the result, so I’m not going to speculate and treat it as an unlikely Plaid gain from Labour.

Support our Nation today

For the price of a cup of coffee a month you can help us create an independent, not-for-profit, national news service for the people of Wales, by the people of Wales.

Notify of
Newest Most Voted
Inline Feedbacks
View all comments
Simon J
Simon J
3 years ago

Thanks for that. It has helped me decide to vote Plaid Cymru in Llanelli.

3 years ago

Tactical? You haven’t even included two thirds of a strategy. Rubbish.Your “tactics” lead to a Labour Plaid Coalition which changes nothing. Disgraceful journalism.

Our Supporters

All information provided to Nation.Cymru will be handled sensitively and within the boundaries of the Data Protection Act 2018.