Gov. Walker: 'Happy Labor Day!'

"Happy Labor Day!" he tweeted.

The tweet made waves, sparking over 200 retweets, 60 favorites and dozens of alternately furious and supportive responses from followers.

Walker drew condemnation from labor groups nationwide after ushering in controversial restrictions on collective bargaining in Wisconsin. 

The effort led to an attempt to recall the governor that was unsuccessful. Walker is now seen as a possible 2016 presidential contender.