FILE - This file photo taken Feb. 17, 2011 shows protestors of Wisconsin Gov. Scott Walker's bill to eliminate collective bargaining rights for many state workers packing the rotunda at the State Capitol in Madison, Wis. (AP Photo/Andy Manis, File)

FILE - In this March 12, 2011, photo, thousands of pro-labor protesters rallied at the Wisconsin Capitol in Madison, Wis. (AP Photo/Morry Gash, File)