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The top 10 seats to watch at the 2021 Senedd election

22 Mar 2021 10 minute read
Mark Drakeford. Picture by Christopher Jones / Alamy Stock Photo. Adam Price. Credit: Euan Cherry/WENN. Welsh Liberal Democrats leader Jane Dodds. Picture by Keith Edkins (CC BY-SA 4.0). Andrew RT Davies picture by the Welsh Conservatives.

Ifan Morgan Jones

And they’re off! The Senedd campaign will start officially on Friday but in practice has already begun, with the main parties all beginning to reveal their policies and promises to the people of Wales.

The election on 6 May will no doubt be the most significant and unusual so far, with the Covid-19 pandemic both raising the profile of devolution and casting real doubt over the turnout and the ability of parties to campaign properly.

There is however plenty to engage us, with recent opinion polls pointing to everything from a near Labour majority to the party’s worst-ever result.

Here are the ten constituency seats that we will be looking at in more detail over the next month. We will also be looking at the all-important regional list in due course.

Lee Waters and Helen Mary Jones. Pictures by Senedd Cymru (CC BY 2.0).


A safe seat for Labour at Westminster, at the Senedd level this is a hyper-marginal with fewer than 1,000 votes separating Labour and Plaid Cymru at all but one of the five Senedd elections.

Labour’s Lee Waters held this seat by just 382 votes in 2016 and is once again facing Plaid Cymru’s Helen Mary Jones, who has stood for the party all five times and won twice.

Despite being a Plaid Cymru / Labour battle, with the votes so close it is what goes on among the other parties here that could be decisive.

The 1,000+ votes for Siân Caiach’s Putting Llanelli First at the last two elections are thought to have cost Plaid Cymru this seat in the past. This time she is standing for Gwlad, a new Welsh nationalist party that may (or may not) have the same resonance.

The two Westminster General Elections since 2016 have also seen a big increase in the Conservative vote in this post-industrial town. Could that eat into the Labour Senedd vote?

Jane Hutt MS is defending the Vale of Glamorgan. Photo by Senedd Cymru

Vale of Glamorgan

This is on paper the Welsh Conservative’s top target seat in Wales and one that they should take if they are going to realistically challenge Labour’s dominance here.

It’s also a seat where the Conservatives have faced a few of their own problems. Alun Cairns, who holds the seat at Westminster, had to resign as Welsh Secretary in 2019 due to the actions of previous Senedd candidate, Ross England.

It didn’t seem to do the Conservatives much harm at the 2019 election however and they will be fairly confident of overturning longstanding Labour member Jane Hutt’s razor-thin 777 vote majority here.

The Welsh Conservatives’ entire M4-focused campaign seems bent on picking up this seat and also possibly Bridgend, another seat they won in their 2019 sweep.

If they don’t win here, it will have been a very disappointing election for them overall.

Education Minister Kirsty Williams is standing down for the Lib Dems.

Brecon and Radnorshire

This seat will see the Liberal Democrats put up the barricades as they aim to defend their very last remaining constituency seat in all of Wales, at both Senedd and Westminster levels.

Kirsty Williams, who has held this seat since 1999, is stepping down, with former Mid and West Wales Assembly Member William Powell the candidate in her place.

Powell has a good story to tell having recently recovered from a spell in intensive care with Covid-19, but the Conservatives and Plaid Cymru have between them gobbled up the Lib Dems’ mid-Wales turf since 2010 and this election could see a continuation of that trend.

On paper, the Liberal Democrats should hold here as they have a healthy majority and won a by-election here in August 2019. With a focused, targeted campaign they should come away with a victory.

But if they lose one of their last remaining foothold in Welsh politics, questions will be asked about how relevant they really are to Welsh politics any more.

Plaid Cymru’s candidate Delyth Jewell. Picture by the National Assembly (CC BY 2.0)


Of Plaid Cymru’s target seats this is perhaps the one where their hopes are highest. In 2016 they closed the gap between themselves and now Labour incumbent Hefin David to 1,575 votes.

Unlike in Llanelli and Blaenau Gwent there has been no obvious internal strife within the party here and Plaid Cymru’s candidate Delyth Jewell has impressed during her two years in the Senedd.

If the party has any real hope of gaining any ground in the constituencies in this election, you feel like this is where it is going to happen.

If it doesn’t happen, Plaid Cymru may end up blaming the Covid-19 pandemic. It’s put the kibosh on local campaigning, the kind of activity that is essential for a party like Plaid Cymru that gets very little attention and air time in the UK media.

Delyth Jewell might have needed five months of campaigning, the kind of activity that led Leanne Wood to victory in the Rhondda in 2016, to overturn the seat. She will now get one month.

Denbigh. Picture by Doug Elliot (CC BY-SA 2.0).

Vale of Clwyd

The Conservatives will want 2021 to be a repeat of 2019 when they swept across the north-east of Wales, picking up a large number of seats in one go.

One of their main campaign messages is that the north of Wales has been roundly ignored by the Welsh Government for 20 years of devolution.

Their best hope of gaining ground is in the Vale of Clwyd where Labour are holding on to a slim 768 vote lead and have a new candidate in Jason McLellan, with Anne Jones stepping down after twenty years.

This seat is now held at Westminster by the Conservatives and like its sister Vale in the south it’s one the Conservatives need to win quite handily if they are to make a serious dent in Labour’s hopes of forming the next government.

Leanne Wood speaking to a member at the Plaid Cymru conference. Picture by Plaid Cymru


This may seem a strange ‘one to watch’ as former Plaid Cymru leader Leanne Wood is defending it with a relatively healthy 14.7% majority.

However Plaid Cymru have won one-off victories in valley seats in the past and then lost them at the next election, so this will be interesting to see whether this victory was a 1999-blip or the start of something long-term for Plaid Cymru in the valleys.

Labour also have a new candidate in Elizabeth Buffy Williams and regaining Rhondda, one of their safest electoral fortresses for going on 100 years, will be a top priority for them.

Wrexham. Picture by Kenneth Allen (CC BY-SA 2.0).


We’re all probably fed up of hearing about the ‘Red Wall’ that crumbled for Labour in 2019, but Wrexham was a key brick in that wall.

This is another of those seats the Conservatives really should be winning if they hope to gain any ground in the Senedd. In fact, their entire messaging at Senedd and Westminster level has been about targetting places like Wrexham – post-industrial areas gradually becoming leafy commuter towns.

They picked it up early in the night with ease at the General Election and unless the Conservatives are in for a terrible night this should be a seat they are nailed-on favourites to flip.

Neil McEvoy AM

Cardiff West

Not every seat in this list is there because they’re likely to change hands. In fact it’s fair to say that – bar a large upset – the First Minister is pretty safe here despite it being on paper a marginal seat.

In 2016 Mark Drakeford came within almost 1,000 votes of being ejected by Plaid Cymru candidate Neil McEvoy, a result which would, looking back, have had quite a big impact on Welsh political history.

Mark Drakeford of course went on to be elected First Minister and led Wales during the Covid-19 pandemic.

Neil McEvoy, elected on the regional list, was kicked out of Plaid Cymru and went on to form his own party, Propel, and is standing again this year.

Plaid Cymru also have their own candidate, Rhys ab Owen, who will be hoping to keep within touching distance of Labour in what should be one of the few seats outside west Wales in which they have a fighting chance.

With Propel and Plaid Cymru splitting their 2016 vote it’s hard to see anything but a comfortable victory for the First Minister.

But it will be interesting to see how that vote splits. Was it McEvoy’s personal brand of populism that carried them so close to the line in 2016, or will those voters stick with Plaid?

Beyond that, the cast of characters alone here makes it a seat worth watching.

Left, Janet Finch-Saunders. Picture by the National Assembly (CC BY 2.0) Left, Aaron Wynne. Picture by Plaid Cymru.


This constituency is very unusual in this election in that it is a seat – the only seat, really – which is a Plaid Cymru contest against the Conservatives in which both could realistically win.

Janet Finch-Saunders is the Conservative incumbent and Aaron Wynne the first time Plaid Cymru challenger.

It’s also something of a three-way contest with Labour only 1,000 votes behind, although they are not currently expected to gain much ground at this election.

The Conservatives should probably keep this seat but it will be interesting to see how the Plaid Cymru v Conservative battle plays out at a local level when both parties will be turning their fire on Labour nationally.

Former First Minister Carwyn Jones. Picture by XIIIfromTOKYO (CC BY-SA 4.0)


This seat should be beyond the Conservatives’ grasp at the Senedd, with Labour defending a healthy 10% majority here.

But the Tories won here at the General Election and long-term incumbent and former Labour First Minister Carwyn Jones is stepping down to pursue other interests.

Bridgend would be a reach for the Conservatives but their levelling up and M4-based message could both play well in this town.

It’s possible however than internal strife may have blown their chances. Experienced Senedd member Suzy Davies has been replaced as the candidate by Vale of Glamorgan councillor Rachel Nugent-Finn.

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