Basil McCrea has confirmed he intends to enter the race to succeed Sir Reg Empey as Ulster Unionist Party leader.
The Lagan Valley MLA said he could turn around the party's fortunes by promoting a strong united message and with changes to its assembly team.
Fermanagh and South Tyrone MLA Tom Elliot has already said he will challenge for the UUP leadership.
Sir Reg said he would resign following a disappointing general election where the party did not win a single seat.
Mr McCrea said: "You cannot win votes back if you are not working on the ground or delivering in the assembly chamber.
"While I wouldn't single out one individual MLA, it is clear that we could do better as an assembly grouping, that we certainly could be more representative both in gender and in age."
Mr McCrea said he was not interested in moving the party closer to the DUP.
Party members will meet on 22 September to select their new leader.