Labour Party (UK):

On 1 March 2014, at a special conference the party reformed internal Labour election procedures, including replacing the electoral college system for selecting new leaders with a "one member, one vote" system following the recommendation of a review by former general-secretary Ray Collins. Mass membership would be encouraged by allowing "registered supporters" to join at a low cost, as well as full membership. Members from the trade unions would also have to explicitly "opt in" rather than "opt out" of paying a political levy to Labour.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". What replaced the "one member, one vote" system?
unanswerable