Watch as Labour leader Sir Keir Starmer speaks in Rutherglen after a by-election victory.
The party’s overwhelming win could put them on course for Downing Street if it is replicated across Scotland, polling expert Professor Sir John Curtice has said.
Labour candidate Michael Shanks won Scotland’s first recall by-election after securing more than twice the votes of his SNP rival Katy Loudon, in results Sir Keir hailed as “seismic”.
Meanwhile, Sir John said that if Labour achieves the same higher-than-expected swing of more than 20 per cent across Scotland at the next general election, the party could win 40 seats north of the border.
The results confirm Labour poses “a serious challenge” to the SNP’s primacy at Westminster and has a momentum comparable with the run-up to the party’s 1997 landslide, according to the elections analyst.
“This is Labour apparently now able to put on the kind of performance that, frankly, it has not been able to put on at any stage since the independence referendum,” he said.