Article Photos: Unions vow political payback for right-to-work law

Union workers hold up a signs during a rally outside the Capitol in Lansing, Mich., Thursday, Dec. 6, 2012 as Senate Republicans introduced right-to-work legislation in the waning days of the legislative session. (AP Photo/Carlos Osorio)

Union workers hold up a signs during a rally outside the Capitol in Lansing, Mich., Thursday, Dec. 6, 2012 as Senate Republicans introduced right-to-work legislation in the waning days of the legislative session. (AP Photo/Carlos Osorio)