Meet Avi Lewis, the leftist firebrand and new leader of the NDP

OTTAWA — Avi Lewis, a polarizing figure within the party who twice failed to win a federal seat in past elections and has never held elected office, is the new NDP leader.

Lewis, a skilled communicator, will face a number of challenges in the coming months, including the need to win a seat in the House of Commons and rebuilding a party that was reduced to just seven seats in last year’s federal election, and has since lost one of its members to a defection to the governing Liberals...