The Stormont Assembly election next week could bring about truly historic political change.

Sinn Féin is widely tipped to emerge as the largest party for the first time in the history of Northern Ireland.

If it secures the most votes and that translates into the most seats, there would then be a nationalist First Minister for the first time.

The party came close last time around in 2017, when 27.9% of first preference votes translated into 27 seats, just one behind the DUP on 28.1% and 28 seats.

A series of opinion polls in recent months and virtually all political observers and commentators north of the border make Sinn Féin a very strong favourite to secure the highest numbers of first preferences.

Whether in a PR election that also results in the highest number of seats will depend on transfers in a few potentially tight contests, with the SDLP and Alliance both targeting Sinn Féin seats.

Michelle O'Neill

The outcome of the Sinn Féin v SDLP battle in the constituency of Foyle, which includes the city of Derry, could be a key indicator as to the outcome of the wider battle with the DUP.

For decades, Derry was the stronghold of the late SDLP leader John Hume, before later becoming the political home of another local man, Sinn Féin's Martin McGuinness.

Sinn Féin stunned the SDLP when it won the Foyle Westminster seat in the British general election of 2017.

However, the success was short-lived, as current SDLP leader Colum Eastwood won it back in 2019 with a majority of more than 17,000.

Colum Eastwood

The extent of the turnaround shocked Sinn Féin.

With ambitions to emerge as the largest party in this year's Stormont election, it feared one or both of the two Assembly seats it held in the constituency could be in danger, and its overall strategy in jeopardy.

There were deep rumblings of discontent within large sections of the Sinn Féin support base in Derry, indicating that there was a deep malaise and unhappiness about how the party was being run in the city.

The party took decisive action last summer, following what was described as an internal review. It effectively sacked its two sitting Stormont Assembly members, including Martina Anderson, a former IRA prisoner and MEP, regarded by many republicans as an iconic figure.

Martina Anderson

"They came in a night of the long knives and ruthlessly changed the party," explains Seamus McKinney, Derry Correspondent for the Irish News.

"It was unusual for Sinn Féin, in that it was a very public bloodletting. On social media, there were many Sinn Féin members who supported what happened, but also many who publicly disagreed.

"Martina Anderson's family actually were very vociferous in their criticism of Sinn Féin. One of her sisters made the point that it wouldn't have happened had Martin McGuinness still been there."

It is understood that some of Martina Anderson's closest supporters have refused to canvass for the party in this election campaign.

The SDLP, which also won two seats in the 2017 Assembly poll, sense political blood. It is fielding its two incumbent Assembly members and a former mayor of the city in a bid to win a third seat by taking one from Sinn Féin.

The nationalist battle in Foyle could have much wider ramifications.

Derry city

"All the opinion polls are saying Sinn Féin is going to come out as the main party after 5 May. In order to do that, they have to - at the very least - hold what they have," Mr McKinney said.

"They can't afford to lose any seats, so it's vital that they hold Derry."

The SDLP will be concerned that the prize of a nationalist First Minister for the first time could influence many of its target voters.

"I still do think that the appeal of having the first nationalist First Minister in Northern Ireland, and giving the DUP a bloody nose, will be a major attraction for nationalist voters, even voters who normally vote for the SDLP,'" says Suzanne Breen, Political Editor of the Belfast Telegraph newspaper.

The DUP is viewed as a party in disarray, with three leaders during the past year and a clear split within its ranks, caused by the way Arlene Foster was ousted in a ruthless coup.

Jeffrey Donaldson

It is also under pressure over its stance on Brexit and the Northern Ireland Protocol, with many unionists and loyalists pointing fingers of blame firmly in its direction.

Jeffrey Donaldson's leadership of the party could come under serious pressure if he is the first unionist leader to finish runner up in the electoral battle with nationalism.

However, the growing expectation that Sinn Féin could make an historic breakthrough also piles huge pressure on the party's leader in Northern Ireland and outgoing Deputy First Minister Michelle O'Neill.

The party has its eyes on leading the government on both sides of the border and a failure to deliver on the Stormont part of that equation would be a huge disappointment.

"They've been ahead in the opinion polls for some considerable time. This is Sinn Féin's greatest chance to emerge as the largest party in Stormont," says Ms Breen.

"If they don't take advantage of it, given all the division that there has been in the DUP, given that Jeffrey Donaldson brought down Stormont, then I think there will be questions asked of the party."

That is a view shared by Mr McKinney.

"They've never been better placed to come out as the top party," he says.

"Everything seems to be going in their favour.

"It seems to be theirs to lose."

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