For Romney, one advantage of the Paul Ryan VP pick is that it moves the needle a bit in Wisconsin. Romney has said that he wants to win Ohio, Florida, Virginia and to take away a blue state.
This survey from the progressive leaning PPP poll shows Ryan making Wisconsin very competitive for the Romney campaign.
The GOP ticket campaigned there yesterday, and Ryan laid it on thick, according to National Journal:
“My veins run with cheese, bratwurst, a little Spotted Cow, Leiney’s, and some Miller. I was raised on the Packers, Badgers, Bucks and Brewers. I like to hunt here, I like to fish here, I like to snowmobile here. I even think ice fishing is interesting,” Ryan said, calling out his favorite state foods and sports teams. “I’m a Wisconsinite through and through, and I just got to tell you how much this means to be home.”
I love this localist name-dropping even when it is so transparently untrue. Does anyone believe the health-nut and P90x-loving Paul Ryan washes down Brats with Miller?
But in any case, winning Wisconsin’s 10 Electoral votes could be one of the narrowest paths to victory for Romney, assuming he is able to make Ohio, Florida, and Virginia fall his way. Then Romney could still lose New Hampshire, Colorado, North Carolina, Pennsylvania and New Mexico, but eke out a 273-265 win in the Electoral College.
Lasorda 
Michael Lewyn 
tbraton 
JonF 
Neal Murray 
I have been saying for several months (on Larison’s blog), in response to arguments that Romney “didn’t have a chance” against Obama, that Romney had a path to victory by adding to the 180 electoral vote base of McCain in 2008 (when those same states carried only 170 electoral votes) the almost certain 11 votes of Indiana and the 75 electoral votes of Ohio, Virginia, North Carolina and Florida. That would take Romney to 266 votes, only four shy of the necessary 270. I just finished reading a Des Moines Register article concerning Obama’s heavy campaigning in that five electoral vote state, which indicates that Iowa is very close. (Recent polls show that the additional electoral votes for the bare-bones minimum electoral victory could come from Colorado.) What I find interesting is that your thinking mirrors mine insofar as Ohio, Virginia and Florida are concerned, but I see you have more doubts about North Carolina than I do. I think North Carolina is more likely for Romney than the other three. After all, it is the state that overwhelmingly rejected gay marriage recently. My concerns about adding Ryan to the ticket (apart from his youth and inexperience) is the deleterious effect it may have on Romney carrying Florida and Ohio, where the proportion of elderly voters is much higher than elsewhere. Elderly voters have always displayed a skittishness when it comes to any proposal that threatens Medicare.