by Patrick Appel
Nate Silver discounts it:
I don’t think there’s been much in the polling data this week that should substantially change your view of the race. Mr. Romney has certainly gotten some encouraging numbers this week, particularly in state-level polls. It’s surprising how much even a one-point shift in the polls can change the way that the race looks and feels.
But from what we can tell, most other candidates have gotten larger bounces after naming their running mates. My gut-level view is that these facts read slightly negatively for Mr. Romney on balance — but I’m not confident enough about it that I’d want to venture much money on that conclusion.