The first results of the Northern Ireland Westminster election are expected by late afternoon today. The future of Ulster Unionist leader Mr David Trimble - and that of the Belfast Agreement - depends on results in several key constituencies.
For the first time, the local government and Westminster elections were held on the same day. Turnout was reported to be high, particularly in West Tyrone where a fierce battle was waged between the SDLP, Sinn Fein and the UUP.
Both SDLP and Sinn Fein sources last night said they were confident of victory. The SDLP ran its high-profile Agriculture Minister, Ms Brid Rodgers; the Sinn Fein candidate was its vice-president, Mr Pat Doherty; and the outgoing UUP MP is Mr Willie Thompson.
There were reports of abuses of the proxy voting system in West Tyrone. SDLP sources said people arriving at polling stations were told they had already been registered for proxy votes. "They had not registered themselves so obviously other individuals were aiming to take their votes," said an SDLP worker.
A heavy turnout was reported in Strangford, with queues developing at polling stations. The DUP's Ms Iris Robinson is aiming to win the UUP seat previously held by the party's deputy leader, Mr John Taylor.
Yesterday's election was the first Westminster poll since the Belfast Agreement. The UUP holds nine of the North's 18 seats. Observers believe that if Mr Trimble loses two or three seats, he will face a leadership challenge.
As well as Strangford, the UUP is also under pressure in North Belfast where DUP secretary Mr Nigel Dodds is favourite to oust the outgoing MP, Mr Cecil Walker. However, the UUP could pick up a seat in North Down, where Lady Sylvia Hermon is favourite to oust anti-agreement UK Unionist MP Mr Bob McCartney. This would offset the possible loss of West Tyrone.
Mr James Cooper of the UUP should hold on to the party's seat in Fermanagh and South Tyrone, although Sinn Fein's Ms Michelle Gildernew is expected to perform well.
The tightest battle between the UUP and the DUP could be in East Londonderry where UUP MP Mr Willie Ross was last night said to be neck-and-neck with DUP Regional Development Minister Mr Gregory Campbell.
DUP sources said victory for its candidates in Strangford, North Belfast and East Londonderry would make Mr Trimble's position untenable. However, pressure is also on the DUP to hold on to South Antrim which the Rev Willie McCrea won in a by-election last September.
Mr McCrea triumphed then by 822 votes with only a 43 per cent turnout. The seat had previously been one of the safest for the UUP. Party sources yesterday said they were confident of recapturing it. However, the DUP insisted it would retain South Antrim.
Although partially overshadowed by the unionist contest, an intense battle also took place for the nationalist vote, particularly in West Tyrone. The SDLP and Sinn Fein are probably competing for runner-up spot in North Belfast and Fermanagh and South Tyrone.
The SDLP is hoping for a strong showing in South Belfast and Sinn Fein is aiming to increase its vote in Newry and Armagh and Foyle.
There was concern among the parties that confusion could have been created by holding two elections, with different voting systems, on the same day.
The boxes will be opened at various count centres across the North at 9 a.m. today. Local government ballot papers will be stored until Monday.
Counting is expected to begin after lunch. The first result is due no earlier than 4 p.m. Barring recounts, all the results should be declared by 8 p.m.