Politics Forget quantum physics, here's how the NDP chooses its leader Add to ... The Globe and Mail Published Wednesday, Mar. 07 2012, 9:00 AM EST Last updated Wednesday, Mar. 07 2012, 12:37 PM EST John Ibbitson explains the preferential ballot system that will determine the next Leader of the Official Opposition Watch More Video: Forget physics, here's how the NDP chooses its leader Uncertain future for South Africa's 'born free' youth Judge approves Bradley Manning name change Raw footage captures herd of elk swimming down river New poll shows Conservatives behind Liberals, NDP in voter consideration By boat? Well, that's one way to deliver mail Bald eagle undergoes extensive surgery in B.C. Florida's homeless-hotel problem overshadowed by Disney tourism boom South Korea releases footage of underwater ferry search Watch as rescue teams save injured crewmen stuck at sea Firefighters injured in Toronto-area industrial explosion Man who killed cop with snowplow 'still dangerous', Widow says South Carolina man apologizes for naked walk through Wal-Mart NATO ships sent to Baltic Sea to bolster defense in region Calgary stabbing suspect held for psychiatric assessment 'Cowboy Indian Alliance' says no to Keystone Snowy Owls draw crowds at Experimental Farm in Ottawa Study shows that nine out of 10 Texans support pot legalization Nigerian schoolgirls still missing a week after mass abduction Affluent prep school grads arrested for running complex drug ring Inquiry begins for cop charged in death of Sammy Yatim Comments AA More Related to this Story Will Cullen be Mulcair's kingmaker in NDP leadership race?