A poll by the Democratic firm PPP finds a 7-point shift toward Mitt Romney in Wisconsin since Romney added Paul Ryan to the ticket. In July, Obama led Romney 50 percent to 44 percent in PPP's poll, but PPP now finds that Romney leads Obama 48 percent to 47 percent (the exact same results of an August 15 Rasmussen poll).

While PPP finds that Democratic voters remain just as committed to Obama, there's been a 10-point shift among both independents and Republicans toward Romney:

The biggest change Ryan's selection seems to have brought about is the unification of the GOP. Romney's gone from a 78 point lead with Republicans on our last poll (87-9) to now an 88 point lead with them (93-5). There's also been a tightening with independents. Obama still has a 4 point lead with them at 47-43, but that's down from a 14 point advantage at 53-39 six weeks ago. Democrats are unchanged from the previous poll.

See Steve Hayes's story from Monday: "The Cost of Ignoring Wisconsin."