Next month’s general election will see Northern Irish voters trudge to their polling stations scarcely three months after March’s assembly elections.

Enthusiasm for another election is scant - both among increasingly disillusioned voters and resource drained parties. Many doubt the general election will produce different results to the recent March vote, with so little having happened since to cause significant swing.

Sinn Féin, however, has reason to be enthusiastic. The conditions for a surprise surge are well in place. A strange mix of factors have aligned which, if the party manages its strategy well, could see it increase its number of MPs from four to seven. This – and expected DUP losses – could see Sinn Féin become Northern Ireland's largest party at Westminster.

This would have major repercussions both in Westminster, as Sinn Féin’s abstentionim means they refuse to take their seats, and at Stormont, by strengthening the party's hand in power-sharing negotiations. March’s snap assembly election saw Sinn Féin surge, with their best ever performance putting them just one seat short of the DUP’s majority.

There were a number of factors behind the surge. Concerns that Brexit could result in a hard border between Northern Ireland and the Republic of Ireland have roused Republican sentiment in the North. And the assembly elections were called after Sinn Féin refused to share power with the DUP due to accusations that the party had been responsible for the mishandling of the RHI scandal, which half a billion pounds of public money misspent.

The populist stance played well with the electorate. Sinn Féin positioned themselves as anti-establishment, anti-corruption and unafraid to hit the DUP where it hurt. The party has also rebranded itself slowly over the course of the last decade as Northern Ireland's social justice party. Of all the region's parties, it is the loudest advocate for marriage equality, and opposes benefits cuts and grammar schools. This has helped endear the party to younger voters more interested in social justice than a longer term goal of a united Ireland.

While the death of Martin McGuinness was a major blow to the party, the worldwide tributes to the former IRA man saw the news agenda dominated by reminders of Sinn Féin's major role in the peace process. This may be more compelling propaganda for the party than any of their own election broadcasts. With such tributes still fresh in their minds as they vote in June, some voters may find themselves steered towards supporting the republicans.

McGuinness’s death may also see some soft nationalists, who previously denounced Sinn Féin due to their historic association with the IRA, now feel their objections are no longer warranted. With Michelle O’Neill, who has never been personally involved with the IRA, having succeeded McGuinness, some may switch from supporting the SDLP to the now less toxic Sinn Féin.

These factors may all combine to see Sinn Féin not only replicate but exceed their strong showing from the March elections.

However, the matter is not only one of overall support. The mechanics of the electoral system will amplify the party’s gains. While the single transferable vote system is used for multi-member assembly constituencies, first past the post will water down the success of smaller parties such as the soft nationalist Social Democratic and Labour Party next month, most likely to Sinn Féin's advantage.

In addition, conditions in three specific constituencies are in place for Sinn Féin to make Westminster seat gains: most likely in Fermanagh and South Tyrone, South Down and Belfast North.

Fermanagh and South Tyrone is one of the most fiercely contested seats in the UK, with a unionist and nationalist divide in the constituency so close you could hardly drive a knife between it. In 2010, Sinn Fein took the seat by a majority of just four votes, following multiple recounts. They subsequently lost the seat by just 530.

However, Sinn Fein saw their Assembly vote share increase by over a thousand votes in the March local election, which, if replicated on 8 June, will see the seat swing back to the party.

The second seat the party could take is South Down. Currently held by the SDLP’s Margaret Ritchie, the party has seen its vote share dwindle in every election of recent times. The party appeared on the cusp of losing one of their MLAs for the area there but they were saved by transfers. Under FPTP, no such last minute rescue can occur.

The third and final seat – Belfast North, home to DUP grandee Nigel Dodds - is perhaps the most unexpected. Few political commentators would have predicted a Sinn Féin victory here even last year. Dodds held the seat with 47 per cent of the vote in 2015, with his nearest rival – Sinn Féin’s Gerry Kelly – securing only 34 per cent.

However, the constituency – like the majority of people in Northern Ireland - voted to remain in the EU and there is growing discontent locally at Dodds' pro-Brexit stance.

Most significant, however, is Sinn Féin's candidate for Belfast North this time round. They are fielding John Finucane, whose father Pat Finucane was a human rights lawyer murdered during the Troubles by loyalist paramilitaries supplemented by alleged British intelligence collusion.

Finucane Senior's death is among the most famous Troubles cases, and his family's campaign for justice has attracted sympathy from both sides of the sectarian divide. Finucane Junior is also a well respected lawyer in his own right. Many soft nationalists and soft unionists in the constituency who would normally vote SDLP, Alliance or Green will now rally round Finucane Junior – meaning there is a credible chance Sinn Féin could pick up a seat from the DUP here. They will be boosted by their main rivals, the SDLP, fielding a little-known candidate in the absence of its popular MLA Nichola Mallon.

In a further boon to Sinn Féin's chances, the DUP also look likely to lose Belfast East to Alliance Party leader Naomi Long. The DUP won the seat after the UUP agreed to stand aside during the 2015 election to avoid splitting the unionist vote. But no such pact has been agreed this time, heightening the chances of an Alliance victory.

This scenario would see the DUP go from eight seats to six, and Sinn Fein from four to seven. The consequences are potentially massive. Should they become Northern Ireland’s largest party, their absence from the Commons could delegitimize Westminster’s discussions on Northern Ireland.

A surge is also likely to have major and long lasting consequences locally. Stormont remains suspended after the collapse of the executive in January. Since then, the party has refused to back down and they have not returned to power sharing despite the March snap election designed to reboot relations at Stormont. Success at the Westminster election would strengthen Sinn Féin's hand in negotiations further.

The punishment the British government imposes for parties refusing to share power at Stormont are either direct rule from London - which the British government, distracted by Brexit, has shown it has absolutely no interest in - or yet another assembly poll. If Sinn Féin finds its prospects boosted by the Westminster election, they may well hold out for the latter, leaving Northern Ireland without a government at Stormont for even longer – and the ever unravelling power-sharing process in limbo yet again.