Labor leaders expect 128,000 volunteers to campaign for President Barack Obama and other union-friendly candidates during the final four days before the Nov. 6 election.
AFL-CIO President Richard Trumka says union members would knock on 5.5 million doors, make 5.2 million phone calls and mail 12 million fliers between Saturday and Election Day.
The union federation is focusing much of its strength in the battleground state of Ohio, where about 13.4 percent of all workers belong to a union.
Unions have a strong campaign infrastructure in Ohio after working last year to pass a ballot measure that repealed a law curbing collective bargaining rights for public workers. That measure passed with 62 percent of the vote.
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