In these first days of Boris Johnson’s Prime Ministership, and with the Brecon and Radnor by-election coming up this week, the latest Welsh Political Barometer poll provides us with an up-to-date assessment of public attitudes in Wales in these eventful political times.

As is always the case, our new poll asked people about their voting intentions for both Westminster and for the National Assembly. Has a change in leadership for the Conservatives, and also for the Liberal Democrats, had any significant impact on levels of party support?

First, lets look at the figures for Westminster. With another general election this year a distinct possibility, how do the parties now stand? Sampling for our new poll began after the outcome for both party leadership elections had been declared, and so provides a gauge of the immediate impact of Boris Johnson and Jo Swinson on levels of party support. This is what YouGov found (with changes from the previous Barometer poll, published just before the European elections in May, in brackets):

Conservative: 24% (+7)

Labour: 22% (-3)

Brexit Party: 18% (-5)

Liberal Democrats: 16% (+4)

Plaid Cymru: 15% (+2)

Greens: 3% (-2)

Others: 1% (-4)

These are quite extraordinary results: in many respects almost wholly unprecedented. The poll shows the extent to which the dominance of the two largest parties has declined in recent months: this is the second Barometer poll in a row where the combined Conservative and Labour vote share is below fifty percent.

In some senses the results of the poll are truly historic. The most obvious concerns Labour’s support: this is the lowest Labour general election support ever recorded in any Welsh poll. Meanwhile, our new poll gives the Conservatives a lead in Wales for the first time since the opening two polls of the 2017 general election campaign; while for the Liberal Democrats, this is their best result in a Welsh poll since the early days of the coalition government in 2010. And such is the dispersal of support across the largest five parties that Plaid Cymru see their support up two points, to a level not far short of an historic high in Westminster support for the party, yet are actually in fifth place!

Projecting parliamentary seat outcomes from polling numbers during such a period of historic turbulence in party support is a very hazardous business. The normal method for generating seat projections – uniform national swings since the last general election – should therefore be interpreted with even greater caution than normal. In a five-cornered general election fight, of the kind indicated by our new poll, all sorts of peculiar localised dynamics might develop in different constituencies. But, for what it is worth, these are the seat projections that are generated from the results of the new poll:

Labour: 18 seats

Conservatives: 16 seats

Plaid Cymru: 4 seats

Liberal Democrats: 2 seats

The majority of the seats to change hands would be won by the Conservatives directly from Labour. The poll projects the Tories to capture Alyn and Deeside, Bridgend, Cardiff North, Clwyd South, Delyn, Gower, Newport West, Vale of Clwyd, and Wrexham from Labour. This is despite the fact that our new poll actually has Conservative support falling by almost ten percentage points since the 2017 general election. Labour support has simply fallen much further. The poll also projects the Liberal Democrats to gain two Welsh seats: Brecon and Radnor (the projection does not take into account this week’s by-election, but the party are projected to gain the seat from the Conservatives simply on the national swing since 2017), and Ceredigion, projected to be gained by the Lib-Dems from Plaid Cymru. Plaid, though, are projected to, in turn, gain Ynys Mon from Labour. Labour’s 18 projected seats would be the first time they had not won a majority of Welsh seats in a general election since December 1918.

The sensational voting intention figures do not stop there. As per usual YouGov also asked about voting intentions for both the constituency and the regional ballots in a devolved election. Here are the findings for the constituency ballot (with changes from the May Barometer poll once again in brackets):

Plaid Cymru: 24% (no change)

Labour: 21% (-4)

Conservatives: 19% (+2)

Brexit Party: 19% (+2)

Liberal Democrats: 12% (+3)

Greens: 4% (-1)

Others: 2% (-1)

These are again figures of historic proportions. This is the first Welsh poll ever to show Plaid Cymru in the lead for the Assembly constituency vote, while Labour support is again at an unprecedented low. Meanwhile, we see support for the Conservatives and Brexit Party apparently edge upwards, and the Liberal Democrats continuing to head back towards the category of a major party.

Once again deploying the assumption of uniform national swings since the last election (the National Assembly election of May 2016), this poll would project the Labour party to lose eleven of the constituency seats that they currently hold. Their projected losses are as follows:

Plaid Cymru are projected to gain Blaenau Gwent, Caerphilly, Cardiff West, Llanelli and Neath

Thee Conservatives are projected to gain Cardiff North, Gower, the Vale of Clwyd, the Vale of Glamorgan, and Wrexham

And the Liberal Democrats are projected to gain Cardiff Central

In addition to these changes, the new poll projects Plaid Cymru to gain Aberconwy from the Conservatives. Labour’s projected sixteen constituency seats would be by far their worst-ever performance at a National Assembly election – they have never thus far failed to win a clear majority of constituency seats in the chamber.

Now the regional list vote. YouGov produced the following results (with changes from May’s Barometer poll once again in brackets):

Plaid Cymru: 23% (+1)

Labour: 19% (-2)

Conservatives: 18% (+6)

Brexit Party: 17% (-6)

Liberal Democrats: 12% (+5)

Greens: 4% (-4)

UKIP: 2% (+1)

Others: 5% (-1)

Once again, the voting intention figures break all previous records. Plaid Cymru have never previously been in first place in a National Assembly poll on the regional list vote. Nor has any Welsh poll ever previously shown Labour support below twenty percent. The figures for this vote also show a significant rise in Conservative support which exactly matches a fall since our last poll for the Brexit party. And, as with the other voting intention results, there is a notable increase in support for the Liberal Democrats.

Allowing for the constituency results already projected, and once more assuming uniform national swings since 2016, our new poll projects the following overall results for the Assembly’s regional list seats:

North Wales: 2 Brexit, 1 Liberal Democrat, 1 Plaid

Mid & West Wales: 2 Brexit, 1 Labour, 1 Liberal Democrat

South Wales West: 2 Brexit, 1 Plaid, 1 Liberal Democrat

South Wales Central: 2 Brexit, 1 Plaid, 1 Liberal Democrat

South Wales East: 2 Brexit, 1 Conservative, 1 Liberal Democrat

These figures therefore generate the following overall projected result for the National Assembly:

Labour: 17 seats (16 constituency, 1 regional)

Plaid Cymru: 15 seats (12 constituency, 3 regional)

Conservatives: 11 seats (10 constituency, 1 regional)

Brexit Party: 10 seats (10 regional)

Liberal Democrats: 7 seats (2 constituency, 5 regional)

In short, this new poll projects the National Assembly heading into uncharted waters – with no party winning even one third of the seats in the chamber; the only two-party majority coalition available being one between the two largest parties, Labour and Plaid; and the Liberal Democrats apparently now on course to re-emerge as a significant force in the Assembly. But in these current uncertain and febrile political times we should be even more cautious than usual about projecting current opinion poll results into future political outcomes. Given how much the fortunes of the parties have changed in recent months, who could accurately predict where they will be by the time of the next Assembly election in May 2021?

Overall, our latest Welsh Political Barometer poll is a fitting reflection of the historic political times that we currently experiencing. This new poll does show some, though modest, evidence of a ‘Boris bounce’ for the Conservatives. If anything, what is most striking is how limited has been the electoral boost for the party from their new leader: new Prime Ministers has historically tended to boost their party’s support by rather more. The poll supports recent Britain-wide polling in suggesting that the Liberal Democrats are back as a significant party – a message likely to be reinforced by the Brecon and Radnor by-election this week. For Plaid Cymru, this is an historic poll: for the first time ever putting them in the lead for National Assembly voting intentions. The poll also shows that the Brexit party has, at least for now, replaced UKIP as a substantial force on the Euro-sceptic right of the political spectrum. Perhaps most significantly of all, though, the new Barometer poll indicates that Labour are in very deep trouble in their most historic heartland. There is no ambiguity about the message of the poll here. This is, on all three voting intention figures, Labour’s worst ever showing in any Welsh opinion poll. Having delivered an unprecedentedly abysmal European election result in May, Jeremy Corbyn and Mark Drakeford now appear to be well on course to destroy their party’s near century-long hegemony in Welsh politics.

YouGov interviewed a nationally representative sample of 1,071 adults in Wales online between 23-6 July 2019.