Ex-PM emerges as unlikely 'saviour' of United Kingdom

Tributes flooded in on Friday for the former Labour leader from the same conservative commentators who once mocked his clumsy style and simmering rivalry with Tony Blair.

Twitter cartoons have even appeared likening him to the superhero Flash Gordon with the slogan: "Gordon's alive!"

Brown "will be celebrated as the union's saviour," read a blog by The Economist, while the Financial Times said: "Scotland these past few weeks has been watching a politician reborn."

The Daily Mail, no friend of Brown when he was in office, hailed him as a "street fighter" and said his campaigning was "stupendous", adding: "Cometh the moment... cometh the man."

The jowly Scot's barnstorming speech on the final day of campaigning on Wednesday was widely shared on social media and was quickly praised as his most impassioned ever.

"Gordon Brown came into his own," said Sean Lang, a senior lecturer in history at Anglia Ruskin University.

Brown made a particularly poignant appeal to wartime patriotism in that speech and portrayed the "No" vote as positive -- something the unionist campaign had failed to do.

"We fought two world wars together. There's not a cemetery in Europe that doesn't have a Scot, a Welshman, an Irish and an Englishman side by side," he said.

"When they fought together, they never asked each other where they came from."

'Passion, energy'

After months of being in the lead, the "No" campaign lost momentum in the final weeks before the vote, prompting Brown to step in and promise to take charge of steering laws granting more powers for Scotland by early next year.

"Voting 'No' will deliver faster, safer, better and friendlier change," he said, appearing alongside his former finance minister Alistair Darling, whose handling of the "Better Together" campaign was criticised as too negative.

Within days, Brown became a central figure on the 'No' side "injecting passion, energy and fresh arguments into a campaign that, before his interventions, was seen to lack all three", said the commentary website, The Conversation.

Asked about a pre-campaign visit to Scotland by the leaders of Britain's three main political parties, Scottish National Party member Gary Cocker said: "They are so unpopular that they can only increase the chances of 'yes'.

"The arrival of Gordon Brown bothers us more. People respect him here."

Brown, 63, graduated from the University of Edinburgh and was first elected to parliament in 1983, alongside Blair.

Together, the men pushed the Labour party into the middle ground and rebranded it "New Labour", securing a landslide victory in 1997.

Brown was Blair's finance minister and took over the top job in 2007, but was voted out in 2010 after the global financial crisis during which he engineered a controversial rescue of British banks.

Brown has remained in parliament representing a Scottish constituency but had appeared to have retired to a quiet life on the back benches and was working on charitable projects.

His performance on the campaign trail has stoked rumours that he could seek a more senior role in the Scottish Labour party.

On the campaign last week, he accused pro-independence SNP leader Alex Salmond of being deceptive.

If he continued with his tactics, Brown said he would be "fighting him and securing the return of a Labour government" in Scotland.