Labour had its worst showing since 1935, prompting Corbyn's decision to step down after two consecutive election losses. The party says its new leader will be chosen by a postal ballot to run from Feb. 21 until April 2. Under party rules, there are several preliminary stages to the contest before it goes to a postal vote of party members.
Corbyn has been criticized for taking the party too far to the left and also for taking a fuzzy approach to Brexit policy, but he retains strong support among the party's rank and file membership. The contest will determine if Corbyn's replacement adheres to his approach or seeks a more centrist platform.
Labour will also choose a new deputy leader at the same time. The party hasn't won a national election since Tony Blair's third consecutive victory in 2005.
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