What does Labour's huge by-election win mean for the SNP and Scotland?

This was a spectacular victory for Labour, and huge loss for the SNP.

Labour’s win is not a big surprise in itself, but the nature of that win surpassed their most ambitious predictions.

Last night during the STV by-election special Labour’s shadow scottish secretary Ian Murray kept adding a few percent to his predictions every time he spoke, receiving silent briefings on his phone from party bosses at the count in Hamilton; or he did until the swing prediction got to 15% and he stopped because it seemed ridiculous.

In the end the swing was more than 20% from SNP to Labour, no-one predicted that.

I’ve spoken before about how Nicola Sturgeon’s resignation levelled the playing field in Scottish politics, but here is the proof.

Scottish Labour candidate Michael Shanks (R) and Scottish Labour Leader Anas Sarwar. Getty Images

In fact, last night’s result suggests that playing field has tilted substantially away from Humza Yousaf’s SNP towards Labour.

Rutherglen and Hamilton West has been a bit of a yo-yo seat since the SNP landslide in 2015, going back to Labour in 2017, SNP in 2019 and now back to Labour; but the nature of last nights result is more like the 2010 result when Labour polled almost 61%.

The SNP’s vote share last night was higher than 2010, more than 10% higher, while the others, particularly the Conservative vote, slumped to a lost deposit.

What this by-election indicates to me is a bit of a realignment of Scottish politics.

With all the SNP’s problems and its change of leadership, Scottish politics is moving away from its constant focus on a constitutional crisis to refocus on the cost of living crisis.

The next general election was never going to be a de facto referendum on Scotland’s future, it was always going to be a de facto referendum on the UK Government.

In the 2010 General Election, Labour won 41 seats in Scotland and the SNP just six.

I don’t think it will be quite that big a gap at the next General Election, but last night the tide turned in Scottish politics.