A committee official tells The Associated Press on Thursday that the committee will air ads in several media markets, including Milwaukee and Green Bay. Republican Sen. Ron Johnson had been considered one of the most vulnerable incumbents against Democrat Russ Feingold, the man he beat six years ago. But private and public polls show a single-digit difference between the two.
Andrea Bozek is a spokeswoman for the committee. Bozek says Wisconsin families fired Feingold once, "and they are going to reject this career politician again."
Republicans hold a 54-46 majority in the Senate but are defending more seats, including several in Democratic-leaning states.
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