Nominations for the general secretary of Unite union formally closed today with two candidates confirmed for the 2013 election.
The current general secretary Len McCluskey and Unite member Jerry Hicks are in the running.
Mr McCluskey announced late last year he was bringing forward the election by some years to avoid a clash with the next general election in 2015.
He was elected in 2010 as the first single general secretary of Unite and has been an active trade unionist since 1968, beginning work as a docker in his native Liverpool.
Mr McCluskey said that Unite "has gone from strength to strength" since 2010.
"I want employers and ministers to understand, very clearly, that as they wage war on ordinary people, Unite will be there to challenge them. This election will give Unite direction and stability over the challenging period ahead."
Mr McCluskey's candidacy has won support from the union's United Left.
Mr Hicks, a one-time Amicus convenor at Rolls-Royce in Bristol, said he wanted to "reconnect" Unite with ordinary union members and pledged he would take only an average wage of around £26,000 if elected.
He said he would also cut Unite's funds to Labour and would give money to the party only after it delivered benefits for union members.
Mr Hicks has recently campaigned for improved pay and conditions for construction workers, and discovered he was included on a blacklist containing over 3,000 names of building workers and environmental activists.
Ballot papers will be sent out next month and the result due in April.
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