Polling guru Sir John Curtice shares his thoughts on Makerfield, Aberdeen South and Arbroath & Broughty Ferry

In two instances, the outcome was markedly at odds with the national political picture. Only in the third was the outcome unexceptional given the national polls.

But that does not mean the two exceptional results can be ignored.

On paper, Makerfield was a golden opportunity for Reform. Two-thirds of the constituency’s voters backed Leave in 2016. Reform were 20 points ahead locally in the council elections on May 7.

Polls conducted during the campaign suggested Reform would win quite comfortably if it had been a general election on Thursday.

Yet Labour – or at least Mr Burnham – was triumphant. Reform only barely increased their share of the vote on what the party secured 2024.

Thanks perhaps to Restore Britain’s ability to win seven per cent of the vote and thereby save its deposit, Reform failed to reach its own stated target of beating the record 38.7 per cent of the vote it secured in last year’s Runcorn by-election.

Meanwhile, defying the near-universal tendency for governments to lose support in by-elections, Mr Burnham increased his party’s share of the vote by ten points.

One of the foundations behind that achievement was a heavy squeeze of the Conservative, Liberal Democrat and Green vote. Those three parties won just three per cent of the vote between them.

In a similar vein, there had been little sign in last month’s Scottish Parliament election of any turnaround in Conservative fortunes in Aberdeen South.

In the two Holyrood seats that lie within the Westminster seat contested yesterday, Conservative support was well down on the party’s support in 2021, in one instance by 7.5 points and in the other by 10.5 points.

These performances were all very much in line with the 10-point fall in support that the party suffered across Scotland as a whole in May.

However, Aberdeen is both the oil capital of Britain and a city that has now fallen on harder times. In the by-election campaign, the Conservatives emphasised their opposition to the reluctance of both Labour and the SNP to facilitate further exploration for oil and gas in the North Sea.

The result was a spectacular success. The first Conservative by-election victory in Scotland since 1973, and the first by-election gain north of the border since 1967.

Meanwhile, at 25 points, the increase in Conservative support since 2024 represented the biggest increase on the party’s standing at the previous general election at any post-war by-election fought at both elections by both Labour and the Conservatives.

The Conservatives’ success seems to have come primarily at Labour’s expense – Labour’s vote fell to a new all-time low in the seat of just 5.4 per cent, although support for the SNP was also down a little.

Labour’s vote fell heavily in Arbroath & Broughty Ferry too. But in contrast to Aberdeen South, the SNP vote rose by six points, while the Conservatives only advanced by four.

That SNP rise gives lie to the suggestion that the conviction for embezzlement of the former Chief Executive, Peter Murrell, has had a discernible adverse impact on the SNP’s Scotland-wide standing.

At the same time, Reform enjoyed a ten-point increase in support – its biggest rise of the night. None of this came as much of a surprise given the outcome of the Holyrood election on May 7 and the parties’ standing in the Scotland-wide polls.

We should always be wary of making too much of exceptional by-election results.

However, Mr Burnham’s success in Makerfield provided ample confirmation that the likely challenger for the Labour leadership has a personal appeal that enables him to reach parts of the electorate that Sir Keir Starmer cannot win over.

While it is unlikely that his arrival in No10, Downing Street, would boost Labour’s fortunes to the same extent as did his candidature in Makerfield, the result gives reason to believe there could be some impact.

Equally, the debate about how best to transition away from oil and gas will not have the same resonance across Britain as a whole as it evidently did in Aberdeen.

However, it does suggest that developing and selling an economic policy that speaks more broadly to voters’ financial concerns might provide a pathway to electoral revival – as well as making the debate about the UK’s energy policy more politically contentious.

Of course, the key question now is just how well will Labour and the Conservatives learn these two lessons?