Nate Silver crunched the numbers and pretty much proved that there is no one Mitt Romney can pick for a running mate who will make any difference whatsoever in the outcome of the election. At least, that is the case if we’re thinking about the candidate swinging their home state from Obama’s column into Romney’s, and thereby changing the outcome in the Electoral College. By Silver’s calculations, the two best options are Governor Bob McDonnell of Virginia and Senator Rob Portman of Ohio, who both max out by changing the outcome of the election 1.9% of the time in 50,000 simulations. McDonnell is the most likely to change the outcome in his home state, but Virginia rarely comes up as the tipping-point state.
This analysis should actually be helpful to Romney, because it should free him up from thinking it matters what state his running mate comes from. It’s almost impossible for that to matter. Far more important is what the running mate can do for the broad narrative of the election. For example, using Silver’s analysis, Tim Pawlenty would be among the worst possible selections, just a shade above Rick Santorum in the disaster category. That is because Minnesotans hate Pawlenty, and selecting him will actually make it modestly less likely that Romney will carry Minnesota. But, in reality, from a statistical point of view, there’s almost no difference between picking Pawlenty and Portman, or McDonnell.
What’s more important than home-state impact is how the candidate will be received by critical swing elements of the electorate, or by the base of the GOP. Tim Pawlenty would excite some elements of the evangelical base without antagonizing suburban women the way the selection of Mr. Forced Vaginal Ultrasound McDonnell would. New Mexico Governor Susana Martinez is very popular in her home state, but her selection would call to mind the selection of another inexperienced and not-well-known female governor four years ago. Sen. Portman would help Romney win Ohio and would probably be well-received by the press, but would help tie Romney’s economic policies to Bush’s economic policies. Each candidate brings unique strengths and weaknesses to the table, but none of them are likely at all to swing the election based on their home state.
