Wisconsin Governor Scott Walker remains the poster child for the war against collective bargaining privileges and other perks for public-sector unions. Although the outcome of last year’s battle was a coup for Governor Walker, it was not without repercussions—foremost being the upcoming recall election. As recently as February, Walker looked quite vulnerable.But the unions can’t claim victory just yet. Buzzfeed reports that one of Walker’s major Democratic challengers, Mayor Tom Barrett, has an anti-union streak of his own, having floated plans to limit collective bargaining by city employees while mayor of Milwaukee. Barrett has pledged to roll back Walker’s policies, but union leaders have already rushed to back his primary opponent, Democrat Kathy Falk.Via Meadia has pointed out that over the past few years Democratic mayors and governors have begun to fight public sector unions nearly as hard as their Republican counterparts, albeit for different reasons: Simply put, the unions are making it impossible for states to meet the needs of those who depend on social and other services.Intrade’s odds now favor Walker winning the recall election on June 5, but, regardless of the outcome, public sector unions now have no shortage of determined foes.