THE unionist hinterland that is Lagan Valley will be an interesting test for Mike Nesbitt's much heralded UUP surge.
It's former position as an Ulster Unionist stronghold was eroded from within, with poll-topping Jeffrey Donaldson's defection to the DUP simply transferring those votes from one party to another.
Donaldson's elevation to Westminster and subsequent withdrawal from the ballot paper has left former health minister Edwin Poots top dog in the constituency, with a first preference vote more than 1,500 higher than his nearest challenger.
That challenger was Basil McCrea, disappointed UUP leadership candidate whose defeat also signalled the end of an Ulster Unionist presence in Lagan Valley when he left the party to form the now-defunct NI21.
Interestingly, the UUP fightback has some echoes of the DUP's power move, involving as it does a high-profile candidate who has defected from the rival party.
In this case, it is DUP whistleblower Jenny Palmer, the Lisburn councillor who left the party after it moved to discipline her following controversy over an alleged attempt by a Stormont adviser to change the way she intended to vote at a Housing Executive board meeting.
She was welcomed into the UUP's bosom in September.
Or perhaps that should be welcomed back, given Mrs Palmer and her husband were originally Ulster Unionists but defected in 2003 during a large-scale exodus over discontent with then leader David Trimble, which also saw the high-profile departures of Donaldson and current DUP leader Arlene Foster.
The scorned party has set pride aside to fast-track the erstwhile unknown councillor onto its ticket in Lagan Valley, and no wonder - by running her they are keeping alive in the memory of the electorate what was a particularly low point for their rivals during the last assembly term.
Whether that new name recognition, coupled with electorate disillusionment with the ruling party will be enough to return a UUP assembly member is unclear.
A lot will depend on where Basil McCrea's personal vote goes, for while it was widely agreed he was unlikely to regain his seat, he enjoyed a certain amount of support in the constituency which, together with the core UUP `vote', could see a win for his former party.
There is even talk of two seats being up for grabs in the constituency, amid rumoured voter dissatisfaction with a hardline local DUP association.
While unlikely - with the UUP vote sinking in Lagan Valley rather than growing - this would be a litmus test of any `surge'.
Meanwhile, boundary changes that did for Sinn Féin in the last election could see the slimmest of chances of an SDLP seat.
Popular former publican and councillor Pat Catney is likely to attract more second preference votes from unionists and Alliance voters in this constituency than his republican rival and could benefit from any shift in the balance of power within unionism.
Perennially popular Alliance assembly member Trevor Lunn should meanwhile hold the seat for his party, perhaps even at an early count.
-----------------
- 2011 share of first preference vote
DUP 53 per cent
UUP 20.4 per cent
All 12.4 per cent
SDLP 6.1 per cent
SF 3.4 per cent
TUV 2.9 per cent
Green 1.7 per cent
- Seats won by party in 2011
DUP 4
UUP 1
All 1
- List of 2016 candidates
Dan Barrios-O'Neill (Green)
Robbie Butler (UUP)
Pat Catney (SDLP)
Jonathan Craig (DUP)
Peter Dynes (Northern Ireland Labour Representation Committee)
Paul Givan (DUP)
Brenda Hale (DUP)
Brian Higginson (Ukip)
Jack Irwin (Conservatives)
Trevor Lunn (All)
Frazer McCammond (Democracy First)
Jacqui McGeough (Sinn Fein)
Jonny Orr (Ind)
Jenny Palmer (UUP)
Edwin Poots (DUP)
Lyle Rea (TUV)
