3) Relationship - Of the four finalists, only Jindal endorsed someone else (Rick Perry), yet all have campaigned publicly for Romney, served as Romney surrogates, raised money for him and been team players since Romney wrapped up the GOP nomination in April. Pawlenty appears to have ingratiated himself with Romney as a low-maintenance, easygoing teammate. Portman was seen as a crucial part of Romney's critical and narrow victory in Ohio and has been a trusted adviser to the Romney campaign for a long time. Ryan, more policy wonk than political animal, recently stepped up his assistance to the campaign and appeared to click with Romney during Wisconsin rallies earlier this year.
4) Governing - The strongest governing choices are Ryan and Portman. Ryan knows the budget better than anyone and has personally authored two budgets as House Budget Committee chairman. Portman is widely respected by members in both chambers for his intellect, experience and calm manner. He served as a legislative aide to President George H.W. Bush before winning a seat in Congress, and was appointed White House budget director and U.S. trade representative by President George W. Bush. Former Gov. John Sununu (R-NH), a senior Romney adviser, told National Review's Robert Costa that Portman is a favorite at Romney's Boston headquarters because of his "political diligence, his fundraising prowess and his policy acumen." Pawlenty and Jindal have very limited Washington experience or relationships, but both have credible reform records as governors.
5) Narrative - The media is more powerful today than ever before. As such, Romney's campaign must consider what the narrative will be for each potential VP choice. For Portman, it will be: insider, Bush baggage, experienced, plain. For Pawlenty, it will be: failed presidential candidate lacking charisma. For Jindal it will be: first Indian American on a major-party ticket, conservative, young. For Ryan, it will be: austerity.
As I said, pundits make predictions. I predict Romney chooses Portman and unveils the before the Olympics in Cincinnati, Portman's hometown. But I'm not wagering money.