Sen. Blanche Lincoln's (D-Ark.) campaign dinged labor groups on Friday for supporting her primary challenger, Ark. Lt. Gov. Bill Halter.

Lincoln campaign manager Steve Patterson lashed out at labor groups, which quickly got behind Halter this week after he announced a primary bid to unseat the centrist Lincoln.

"If we want to talk about misleading advertising, we might look at Bill's first ad," Patterson told TalkBusiness.  "It puts a football in his hands and highlights his humble roots when in fact, he's a multimillionaire who somehow talked labor unions into paying off a half million dollar campaign debt to himself with the union dues of their members so he can run for higher office."

Lincoln had been seen as a key swing vote on some top priorities of labor in the past year and a half, including stimulus and jobs packages, healthcare reform, and on the Employee Free Choice Act (EFCA, or "card check").