The principality's four female MPs and two MEPs are spearheading efforts to ensure a gender balance in the assembly by "twinning" constituencies, as is being done in Scotland for its new parliament.
Under the twinning procedure, members choose a man and a woman to represent constituencies that are "paired" according to their likely winnability. But constituencies angry that twinning would remove their autonomy over candidate selection have proposed an alternative selection process which will be debated at the party's Welsh conference tomorrow.
They are claiming backing from the Lord Chancellor, Lord Irvine, who has said that twinning may be illegal under sexual discrimination legislation.
Under the alternative, all constituencies would choose a man and a woman and the party's selection board, which vets proposed candidates, would decide who got the seat. Proponents argue roughly equal numbers of men and women should be adopted, achieving the same aim as twinning but more democratically.
Garry Owen, a Welsh executive member and president of the Pontypridd constituency which has proposed the alternative, said it was "practical, workable and flexible". Twinning was divisive, he said. It could mean, for example, that a larger constituency could disenfranchise a smaller neighbour.
Jeff Hopkins, Llanelli constituency secretary, said they were in favour of equal opportunities, but there was not a big pool of women available in Wales because they had not taken part in politics before. "In terms of politics [women] need education ... so that they understand that there's a system there that they can use," he said.
However, several party members said it was "traditional" constituencies in places such as the valleys who were opposing twinning. "The only way [the Pontypridd alternative] can achieve a gender balance is by a barter with all the old power brokers," one said.
Chris Roberts, of the "twin to win" campaign, said half the constituencies had signed up in support and they believed many union votes would go their way.
"Given the democratic deficit as far as women are concerned, we think the slight disadvantages of twinning are worth the great advantages it will secure in producing a truly representative assembly," he added.
Julie Morgan, MP for Cardiff North, pointed out only four out of forty MPs were women, three of whom were selected from the now-banned all-women shortlists; 19 per cent of councillors were female, a lower proportion than in England and Scotland. Ensuring there were women in the new assembly was a way of changing the "totally male-dominated" politics in Wales, she said.
The Welsh Equal Opportunities Commission is currently investigating the "substantial under-representation" of women in Welsh political life and intends to present its findings on the problem to the Government.