That leaves the issue of experience. The Presidency is a job like no other. Romney is a capable individual with a variety of experience, but there is little doubt that he will find very steep learning curves with many aspects of the Presidency. At a recent forum at the Brookings Institute, Ambassador Chase Untermeyer, who was an assistant to Vice President Bush and then head of Presidential Personnel in the George H. W. Bush White House, observed that Capitol Hill experience should be a pre-requisite for the vice presidency. The last two vice presidents who came from governorships to the vice presidency were Agnew and Rockefeller – both had difficult experiences in their new role. Congress is a unique institution and a new president who does not know it well himself will need counsel and will probably benefit from his VP’s personal contacts.
In terms of Hill experience the leaders, by far, are Rep. Ryan and Sen. Portman. Both were elected to the House of Representatives seven times. But Portman was also elected to the Senate and has the additional virtues of substantial executive experience close to the White House as a staffer, OMB chief, and US Trade Representative. All of these positions are in areas where Romney may find that he needs an experienced hand to offer assistance and advice.
On the one aspect of the VP selection process that is clear to outsiders (resume) Portman has a strong lead. But there are many other factors – including the all-important issue of personal chemistry.It occurs to me, I did not address the question of Chris Christie. He is a talented politician and interesting character. But he has been governor of New Jersey for less then 3 years. Prior to that he was US attorney for New Jersey for six years. This is important experience, but not electoral experience. Most importantly, Christie's background suggests little that substantially augments areas where Romney is weak - experience with Washington and international affairs.
Another candidate worth a bit more examination is Louisiana Governor Bobby Jindal. He has a bit of Washington experience - 3 years in the House and 2 years as Asst. Secretary at HHS. He is an extraordinarily capable politician and young enough to have multiple shots at the presidency himself. But his Washington experience is slender and offers Romney little complementary experience.
Finally Rubio also has only two years of Washington experience, thus not bringing the right skill set to the table.