Speaking to reporters after touring a Boeing plant in South Carolina Monday, Republican presidential candidate Mitt Romney pledged to pursue legislation that would prohibit unions from contributing dues to political campaigns.

"We have a very unusual circumstance in this country," Romney said, "and that is that we allow union bosses to collect dues from union members and then to use that money as the union boss sees fit to elect people who might do their bidding. It's unseemly at best."

"I will pursue and hopefully enact legislation which inhibits taking money in the form of dues and putting it behind political campaigns. That should not happen."

The candidate added that he had "no problem with unions."

Watch this video from CNN, broadcast Sept. 12, 2011.

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