The Democratic firm Public Policy Polling finds the race in Wisconsin essentially tied at 48 percent for Mitt Romney to 47 percent for President Obama. That's a seven-point swing from last month's automated poll, when Obama led 50 percent to Romney's 44 percent.

Paul Ryan and Mitt Romney. (Melina Mara)

At 49 percent approval in the poll, Rep. Paul Ryan is the most popular person running on either ticket in his home state.

“Wisconsin really is starting to look like a toss up in the Presidential race,” PPP President Dean Debnam said. “The big question is whether this is just a bounce from Paul Ryan’s selection as running mate, or if the increased Republican competitiveness will prove to be lasting.”