Alex Salmond is a man well-acquainted with political comebacks but I’m not sure this one can really be added to his list. Surely one needs to leave the spotlight for a little longer than two weeks for it to count as a comeback? Perhaps add a space – he has ‘come back’, as one does from a holiday.

Salmond’s announcement over the weekend that he will seek a return to the House of Commons came as a surprise to almost no-one. Since his resignation speech on September 19th, he has been clear that he was “not retiring” and would “continue to represent the people of the North East of Scotland”. He has also stressed the importance of “holding Westminster’s feet to the fire” on more powers for Scotland. Additionally, it makes sense for him to get away from Holyrood so as not to overshadow Nicola Sturgeon.

Not to mention the fact that, although he and his party have come to use the word “Westminster” as a term of derision, many who have observed him there opine that he actually rather likes the place. It will not be the first time he has made a swift return there after handing over the SNP leadership – he did the same in 2000, though on that occasion he had never actually relinquished his Westminster seat.

This time he needs to fight an election to ensure his safe return to the green benches. He has chosen the Gordon constituency, where the retiring Sir Malcolm Bruce won a majority of almost 7,000 for the Lib Dems in 2010. The seat fits Salmond’s North East criteria and overlaps slightly with the Aberdeenshire East constituency he represents in Holyrood. Current Scottish polling suggests that he will take the seat for the Nationalists quite comfortably. Whether he would have found it quite so easy had Bruce, who has held the seat since 1983, not been standing down is another matter. The loss of incumbency advantage is a major blow for the Lib Dems.

Despite tactical voting, given the expected downturn in Lib Dem support and surging momentum behind the SNP, combined with Salmond’s ‘celebrity’ factor, it would be a brave soul to bet against him.

But it is worth a note of caution. In 2010, Labour polled 20% of the vote and the Conservatives 19%, just a little way behind the SNP on 22%. Bruce took the seat with 36%. It is not beyond the realms of possibility that tactical voting by Labour and Conservative voters could keep Salmond out, or certainly ensure that he doesn’t have a walkover on his hands. Bear in mind also that voters in Aberdeenshire rejected independence by a 60-40 margin.

All that being said, given the expected downturn in Lib Dem support and surging momentum behind the SNP, and combined with the Salmond ‘celebrity’ factor, it would be a brave soul who bet against him taking the seat. So what role will he play in Westminster?

Ultimately it depends on two factors: firstly how well his party does in the rest of Scotland; and secondly how close the national result across the UK is.

In a hung Parliament, a group of 20+ SNP MPs would give the party a potentially decisive say in who forms the next UK government. They have made clear that they will do anything they can to keep the Conservatives out, but would consider other “progressive alliances”, most likely on a ‘supply and confidence’ rather than formal coalition basis.

In those circumstances, though Salmond would not (we assume) be the formal leader of the SNP group at Westminster, his profile and experience means the media and public would look to Salmond rather than Angus Robertson as the man to give the thumbs up to a possible Labour minority government.

There are a lot of variables in all this. As I have written on these pages before, there are numerous obstacles in the way of the SNP procession to Westminster.

But if the cards fall his way, Alex Salmond may once again hold the fate of the UK in his hands.