The left-leaning party has dominated Welsh politics since the inception of devolution in 1999. But, like with the Scottish Parliament, its iron grip on power may be slipping as disillusioned voters increasingly look for alternatives.
A YouGov poll for ITV and Cardiff University found that its support has slumped to 32 percent of the vote in the constituency section of the ballot.
This is down two points from the last poll in January, while the Conservatives sit on 30 percent (+4).
Plaid Cymru is in third place on 23 percent (+1) the Liberal Democrats on 5 percent (+1), Reform UK on 3 percent (-2), the Greens on 2 percent (-4) and Others on 5 percent (+1).
It also gave Labour (31 percent – a change of +1) a narrow lead over the Conservatives (28 percent – a change of +3) in the regional section of the ballot ahead of May’s vote.
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“Even in difficult years for Labour, none of their opponents have yet been able to come close to defeating them for first place.
“But the evidence from our latest poll does suggest that Labour’s dominance may be challenged more strongly than ever before in 2021.”
Professor Scully said it also found that the Welsh Conservatives had shown “clear improvement” to the detriment of First Minister Mark Drakeford’s party.
While adding a note of caution he pointed out that findings were very close to another recent poll of Welsh voters.
“They are also very much in line with the changes seen in recent Britain-wide polling, which has suggested some strengthening of the Conservative position and a modest Labour decline,” he added.
“The polling continues to indicate that there are three major parties in the contest for the Senedd.
“But Labour’s status as the leading one of those parties no longer looks as if it can be taken for granted.”
The poll will be dire reading for many Labour members, who were hoping for a revival under new leader Sir Keir Starmer.
Despite ditching Jeremy Corbyn after Boris Johnson’s landslide victory in December 2019, it appears that it is still struggling to connect with ordinary voters.
This problem contributed to once-loyal working class communities in northern England deserting the party for the Tories in their droves.
The seismic shift has already happened in Scotland, where New Labour dominated before being routed by the SNP in 2015.
This electoral revolution could now happen in Wales, once Labour’s unquestionable heartland.
The Welsh Political Barometer poll, for ITV Wales and Cardiff University, had a sample of 1,174 Welsh adults aged 16+ and was carried out online by YouGov between March 16 and March 19.