Today is the final day for voters in North Antrim to seek a by-election over Ian Paisley Junior's failure to register free family holidays in Ski Lanka.
If 10% of the constituency electorate, around 7,500 voters, have submitted petitions over the past six weeks, a by-election will be triggered.
It is the first time in the history of the Westminster parliament that this facility has been made available to voters.
The counting of the signed petitions will take place at the Northern Ireland electoral headquarters in Belfast immediately after midnight and a result is expected at 2am tomorrow.
Mr Paisley is currently serving a 30-day suspension from Westminster and he has also been suspended from the party founded by his late father, while the DUP carries out further investigations.
The Commission for Standards in the House of Commons had recommended the Westminster sanction over the non-declaration of hospitality from the Ski Lankan government.
The details of two free family holidays were uncovered by the Daily Telegraph newspaper last year.
Members who are suspended from the Commons for more than 21 sitting days are open to a recall petition.
The Recall of MP's Act became law in 2015, following pressure for the measure after several controversies over members' expenses.
If a by-election is triggered, Mr Paisley will be entitled to contest it. He received over 28,000 votes, 58.9% of the vote, in last year's Westminster election and had more than a 20,000 surplus over his nearest challenger, Sinn Fein's Cara McShane.
For the past six weeks centres have been opened in Ballycastle, Ballymoney and Ballymena where voters could submit a recall petition and a postal facility has also been available.