From CNN.com article:
“You remember when Ryan stood up in front of nation during the Republican National Convention and blamed the president for a plant closing in Janesville, Wisconsin? Yeah, turns out the closure was planned before Obama even took office. The people in Janesville knew the truth, which is probably why more than 60% of the county it’s in voted for Obama.” (reference link)
Here’s a link to Rock county’s election results: http://www.politico.com/2012-election/results/president/wisconsin/#county55105
Janesville, Wisconsin resides in Rock county.