The staffers from New Democrat MPs' parliamentary and constituency offices have voted to join the United Food and Commercial Workers.
They had been members of Unifor, the country's largest private-sector union, but divorce proceedings were instigated after Unifor refused to give unconditional support to the NDP in the Ontario election last spring.
Unifor encouraged its members to vote strategically — for either the Liberals or NDP — to ensure the Progressive Conservatives didn't win.
It has since adopted a similar strategy for next year's federal election in a bid to defeat Stephen Harper's Conservative government.
Federal NDP staffers decided Unifor could not be relied upon to protect their jobs if it wouldn't give a blanket endorsement to the party for whom they work.
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