UUP politician Basil McCrea is pitching himself as the anti-establishment candidate for the party leadership.
And he believes Ulster Unionist grandees fearful of his chances are plotting a ‘Stop Basil’ campaign.
Mr McCrea, MLA for Lagan Valley, has confirmed the worst kept secret in Northern Ireland politics by declaring his intention to stand for the party leadership.
Up against him in the race to succeed Sir Reg Empey is Fermanagh Assemblyman Tom Elliott (right).
Mr McCrea told the Belfast Telegraph: “I recognise that Tom has the backing of the party establishment.
“My message is that the grassroots are increasingly disillusioned with a leadership that's not able to get us any results.”
He also said: “I am also aware that there are senior party members in a 'Stop Basil' campaign.”
The leadership election will be decided by a vote of party members at a meeting on September 22.
Mr Elliott is expected to launch his campaign later this week and is highly likely to have the backing of a large section of the UUP Assembly team.
Mr McCrea is banking on a grassroots revolt, in the wake of years of decline and a disastrous General Election campaign that left the party without a single MP to its name.
Speculation about a mystery third name entering the race has diminished in recent weeks.
The issue of unionist unity will be one of the main debating points between the two leadership hopefuls.
Mr McCrea has ruled out forging closer links with the DUP, a stance he believes has strong backing among rank-and-file Ulster Unionists.
Mr Elliott favours co-operation between the two unionist parties but is opposed to any talk of a merger.
The two men are viewed as from different wings of the party, with Mr McCrea seen as more liberal and Mr Elliott having a rural, Orange Order background.
Mr Elliott should in theory start in a strong position, given the extent of his support from the party's upper reaches.
However, the fact that the decision rests on a vote by individual party members makes the outcome very hard to predict.
Party veteran John Taylor was viewed as the clear favourite to succeed Jim Molyneaux as Unionist leader in 1995.
However, he lost out on the night to David Trimble in a decision that was to have major implications for the party’s future.