Tactical voting – Did it stop Reform?

Mike Hedges – MS for Gŵyr Abertawe

During the 2026 Senedd election campaign there was one major topic of discussion – how do you vote tactically to stop reform?

We know that Plaid Cymru won forty-two seats and Reform thirty-four, Labour 9, Conservatives seven, the Green party two, and the Liberal Democrats one.

Voters were given one ballot paper, rather than the two previously used in Senedd elections, and voted for one political party or an independent candidate, rather than individual candidates, resulting in voters being unable to vote for a specific candidate.

Even before votes were counted in this year’s Senedd election, speculation among commentators was that one campaign narrative had firmly taken hold, that the contest had become a “two-horse race” between Plaid Cymru and Reform UK.

Every British general election since 1945 Labour and the Conservatives have come first or second but with different winning margins. I do not recall a general election that has ever been described in the manner of the Senedd election as a two-horse race.

Both parties promoted the two-horse race narrative during the campaign, urging voters to see the election as a straight choice between them. Following the result and Labour’s substantial losses, attention quickly turned to whether the media had promoted that message and affected the result.

Analysis published on Nation.Cymru of election coverage found that more than one in four TV news items featured an opinion poll, often framing the contest as a battle between the two parties, using “it is a two-horse race”.

On UK-wide main bulletins, that figure rose to more than half. In the final week of the campaign, almost half of all TV news items referenced a poll.

There were no constituency opinion polls, only all Wales polls many from a self-selected panel.

Slogans

From the outset Plaid Cymru and Reform used campaign slogans that presented the election as a direct battle between the two parties. The clear message was that voters should back one of the frontrunners rather than waste their vote on other parties.

That framing carried particular significance because this election was held under a new proportional voting system which much of the electorate did not understand.

Unlike Westminster’s first-past-the-post model, proportional systems are designed to produce representation for multiple parties because seats are allocated according to vote share. The election based on the new system could not have been further from a two-horse race.

Stronger performances by Labour, the Conservatives, Greens, or the Liberal Democrats could have translated into greater representation in the Senedd.

The public understanding of the new system remained limited with the system not understood by most of those I talked to.

Conversations with voters such as, “I always vote for you and Labour, but I have to vote Plaid Cymru to stop Reform” were common.

Surveys conducted before and during the election suggested widespread confusion about how votes would translate into seats, alongside misinformation about tactical voting.

Media

Research has long suggested that heavy reporting of opinion polls can concentrate support around leading parties, encouraging tactical voting and creating a bandwagon effect as voters gravitate towards parties perceived to be gaining momentum.

The available seats were then distributed proportionally to the parties based on how many votes they received, electing the candidates in the order on their ranked party list.

The single ballot paper showed the list of candidates next to each party in order, therefore showing all the candidates in a constituency on the ballot paper.

I intend to examine each of the sixteen constituencies and see how tactical voting helped or hindered reducing Reform’s and Plaid Cymru’s number of members elected.

Where the sixth seat was not won by the Labour or Conservative parties how many Plaid Cymru votes would Labour have needed and how many Reform votes would the Conservatives have needed to win the sixth seat without affecting the other five seats.

In most seats a small change in votes would not have affected the result. In the seats I discuss below a small movement of votes would not have affected the first five seats but would have affected the sixth.

In the Blaenau Gwent Caerphilly constituency 216 Plaid Cymru voters voting Labour would have meant Labour winning the sixth seat not Reform.

In Brycheniog Tawe Nedd less than two thousand Plaid Cymru voters voting Labour would have meant Labour winning the sixth seat not Reform

In Clwyd for Labour to have won the sixth seat rather than Reform, Labour needed three hundred people who voted Plaid Cymru to vote Labour.

In Gwyr Abertawe less than two thousand Reform voters voting Conservative would have given the sixth seat to the Conservatives not Plaid Cymru.

In Sir Caerfyrddin for Labour to have won the sixth seat just under three thousand Plaid Cymru voters would have needed to vote Labour to stop Reform winning the sixth seat.

Efficient tactical voting would have stopped Reform winning four seats and Plaid Cymru one with Labour winning four and the Conservatives winning an extra seat.

So in over a quarter of seats targeted tactical voting would have worked.

In five of the sixteen constituencies tactical voting produced a different result to what the voters said they wanted.