Northern Ireland's Finance Minister Arlene Foster has been confirmed as the only candidate to succeed Peter Robinson as leader of the Democratic Unionist Party.
The deadline for nominations closed at 5pm.
The Fermanagh and South Tyrone MLA, who made a high-profile defection from the Ulster Unionist Party in 2004, has also been endorsed by the party's deputy leader, Nigel Dodds, who ruled himself out of the running for the top job on Monday.
Mr Robinson, 66, announced his intention to resign as DUP leader and Stormont First Minister last month, days after signing a political deal with Sinn Féin and the British and Irish governments to stabilise the rocky power-sharing administration in Belfast.
If Ms Foster is elected party leader there would be a degree of expectation that she would become Northern Ireland's new First Minister as well.
Mr Dodds' decision not to run came as a major shock, as there had been widespread speculation that he would become the new party leader and would then nominate Ms Foster as the new First Minister.
East Antrim MP Sammy Wilson had originally said he was not going to run for leader and backed Mr Dodds for the post.
However, after his colleague signalled he was not going to run, he said he was going to reconsider his decision.
Mr Wilson said after reflecting on the matter he still felt it best not to stand.
"When I balanced it all up and looked at the pros and cons and the arguments for and against, I just felt it was better there shouldn't be a contest at this time," he said.
"I am willing to work with Arlene once she becomes leader."
The DUP's MLAs, MPs and sole MEP are due to meet to officially select their new leader in an east Belfast hotel next week.