Vice President Joe Biden addresses the NAACP annual convention, Thursday, July 12, 2012, in Houston. (AP Photo/Pat Sullivan)

DETROIT (AP) — Vice President Joe Biden is telling unionized workers that he and President Barack Obama have their backs.

Biden used a Labor Day rally in Detroit to encourage organized labor to take a critical look at Republican presidential nominee Mitt Romney and running mate Paul Ryan. Biden says they don't appreciate the role union workers played in building the country and instead vilify their work.

Biden also says Romney and Ryan don't believe in workers' rights to collective bargaining.

Biden commented as Democrats prepare to open their convention Tuesday in Charlotte, N.C., where they will nominate the Obama-Biden team for a second term. The choice of Charlotte had roiled union leaders who noted that it doesn't have a single unionized hotel.

Associated Press
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