Suzanne Breen: Five things to watch for when the votes are cast
Five things to watch for when the votes are cast
First test for SDLP-Fianna Fail
This is the first electoral test for the SDLP since its new partnership with Fianna Fail was announced three months ago.
SDLP leader Colum Eastwood and deputy leader Nichola Mallon are hugely enthusiastic about the move. Today we'll see whether nationalist voters agree with them.
We will be bringing you live results from every count centre - Visit our Election hub - and check out the results as they come in from each council - Antrim and Newtownabbey --- Ards and North Down --- Armagh City, Banbridge and Craigavon --- Belfast --- Causeway Coast and Glens --- Derry and Strabane --- Fermanagh and Omagh --- Lisburn and Castlereagh --- Mid and East Antrim --- Mid Ulster --- Newry, Mourne and Down
The Fianna Fail link-up seems an easier fit in rural areas than in Belfast. Confusion about what exactly the new partnership means doesn't help, with the SDLP appearing neither fish nor fowl in the eyes of some voters.
The decision by former Foyle MP Mark Durkan to run for Fine Gael in Dublin in the European election has muddied the waters even further. The SDLP seems under greatest pressure in Belfast where it's highly unlikely to return with the seven seats it won in 2014.
Can Alliance break through 10% barrier?
Local government elections are where you'd expect the Alliance Party to thrive but the party hasn't polled strongly in them over the past four decades.
In 1977, Alliance secured an impressive 14% of the vote but it was downhill from then on. The party won just 5% support in the 2001 and 2005 polls before making modest gains and climbing to 7% five years ago. Naomi Long is aiming to break through the 10% barrier this time round and surely stands a good chance. She will be hoping to make inroads among SDLP urban supporters not keen on the partnership with Fianna Fail and among unionist Remainers.
Alliance is standing more candidates west of the Bann. There has been a huge push to have Stephen Donnelly elected in Omagh but it's too close to call.
DUP lesbian candidate
All eyes will be on Alison Bennington, the DUP's first openly gay candidate, who is running for Antrim and Newtownabbey Borough Council.
While the vast majority of the party's new younger voters seem liberal on social issues, the Save Ulster From Sodomy strain still prevails with the party's traditional base. Ms Bennington was selected centrally by the DUP and if she polls well it will strengthen the hand of the party's more pragmatic, modernising wing.
DUP MLA Jim Wells said the Rev Ian Paisley would be aghast at the move, which he reported had caused discontent across the party. If he's even partially right, the TUV are likely to benefit.
When Barry McElduff resigned last year amid outrage after he posed with a loaf on his head on the anniversary of the Kingsmill massacre, it appeared that his political career was over.
But 16 months later, the former Sinn Fein West Tyrone MP is back. His performance in the Omagh Town ward of Fermanagh and Omagh District Council will be one to watch.
Mr McElduff was a hugely popular politician with republican grassroots in the area, many of whom accused the party of abandoning him. In the by-election which followed his resignation, Sinn Fein's vote fell by almost 6,000 as some supporters loyal to the former MP choose to stay at home rather than vote for his replacement Orfhlaith Begley.
Aontu, the party set up by former Sinn Fein TD Peadar Toibin, could also poll strongly in rural areas, talking votes from both Sinn Fein and the SDLP. But across Northern Ireland, Sinn Fein is very upbeat and the party is confident of getting out its vote.
The last council elections saw what's a rare occurrence: a small advance for the UUP, which secured 16% of the vote to the DUP's 23%. The relative proximity of the gap between the two is something that Robin Swann's party can only dream of nowadays.
He rightly escaped responsibility for the UUP's poor performance in the 2017 Westminster election; he'd just taken over the reins from Mike Nesbitt. This time round will be different. The UUP isn't talking of making gains but rather of consolidating its vote and seats.
However, some decisions, such as running two candidates in the Belfast ward of Lisnasharragh and potentially putting at risk the seat of veteran councillor Chris McGimpsey, are questionable.
The publication of the RHI report before yesterday's election would have hugely helped the DUP's main rival. Its best hope is for disillusioned DUP voters to reluctantly lend it a vote or to stay at home in protest at the Stormont stalemate.
A significant fall in the UUP vote would set alarm bells off for the chances of its candidate Danny Kennedy in the upcoming EU election.