John King breaks it down…

Honestly, this doesn’t surprise me.

While Wisconsin leans left, when voter enthusiasm isn’t up…it’s tight. Kerry barely won it in 2004 and Gore’s margin was even closer in 2000. Obama ran away with it in 2008, so it remains to be seen if Ryan can make that big of an impact on the race. These numbers show that he may already be doing that.

Also, you have to consider that embattled Governor Scott Walker had recently successfully battled back against the recall efforts…so the conservative base is fired up.

Here’s more from CNN:

According to the CNN/ORC International survey, which was conducted entirely after Romney added Ryan to the GOP ticket, 49% of registered voters in Wisconsin say they back President Barack Obama, with 45% supporting Romney. The president’s four point advantage over the presumptive Republican presidential nominee is within the survey’s sampling error.

Two other polls conducted last week, before the Ryan announcement, indicated the president holding a single digit advantage in a state he won by 14 points in the 2008 presidential election.

Wisconsin now becomes the eighth state CNN considers a true toss up, joining Colorado, Florida, Iowa, Nevada, New Hampshire, Ohio and Virginia. CNN considers Michigan, New Mexico, and Pennsylvania as states that lean towards Obama, with Arizona, Indiana, Missouri and North Carolina as states that lean towards Romney.

Obama won all of those toss up states in 2008, which is why he thumped McCain. Looks like it won’t be like that this year, at least in Wisconsin.

More as it develops…

Politics CNN VIDEO: Wisconsin Moves To Toss-Up