The Progressive Democrats have agreed new rules to elect a leader, which offer less than one third of the vote to ordinary party members.
The changes were agreed by an almost two-thirds majority during a special party conference in the Green Isle Hotel, in Dublin, on Saturday afternoon.
A rules committee, headed by Mr Tadhg Kearney, had recommended that TDs, MEPs and elected senators should have 40 per cent of the votes in an electoral college.
The party's 3,000 members, the committee proposed, should control 40 per cent more, while the remainder should be held by appointed senators, councillors, national executive members, and trustees.
Following two hours of debate, however, the conference amended the proposal significantly, cutting the rank-and-file's share down to 30 per cent.
In addition, it decided that all senators, whether elected or included as one of the Taoiseach's nominations, should have an equal voice.
The share of the electoral college controlled by the party's elected officers, on the other hand, should be increased to 30 per cent, the meeting decided.
Speaking later, the Tánaiste, Ms Harney said: "I think it is a fairer system than one person, one vote which was one of the alternatives discussed in the run-in to the conference.
"That had a lot of dangers. It has some attractions, naturally. Some members of our party feel that they should have equality with elected members of the Parliamentary Party, but I think it is open to a lot of abuse. It could be particularly so in a small party like ours. So I think the weighting agreed is an honest system. I think the outcome will be very representative of the party," she told The Irish Times.
