WASHINGTON — The most striking thing about the current Republican vice presidential field is its striking superiority to the Republican presidential field of six months ago. Former Gov. Jeb Bush, Sen. Marco Rubio, Gov. Chris Christie and Sen. Rob Portman are among the more accomplished, knowledgeable, ideologically balanced political figures in American politics. The same could not be said of Rick Perry, Herman Cain or Michele Bachmann.
The untested, of course, are also unwounded. It is easier to appear qualified and dignified when you haven't been stripped, prodded with sharp sticks and forced to perform tricks on dozens of debate stages.
But there is more at work in this obvious stature gap. Part of the explanation is structural. Presidential candidates are largely self-selected, which favors ambition and self-regard above, well, all other traits. A vice presidential field results from a party's consensus on talent and competence.
A portion of the gap, in this case, is also cyclical. The presidential timing for Bush, Rubio or Christie — for a variety of personal and political reasons — was premature. The strong Republican vice presidential field of 2012 is also the strong Republican presidential field of 2016, just coming into its own.
Yet Mitt Romney's realistic shot at the presidency could make his vice presidential choice a golden ticket — essentially ending the contest for the Republican future before it actually begins. Any Republican on the current list who is elected vice president would become the party's presumptive presidential nominee after Romney's service. And Romney is very likely to keep to the current list. John McCain's experiment in surprising, symbolic boldness is too fresh and painful to be repeated.
How should Romney make his choice? Political science offers some guidance. There is little evidence that choosing a running mate to gain advantage in his or her home state or region makes any difference. The contrast between the presidential candidates overwhelms local pride in a prospective vice president's voting address. But the choice of a running mate seems to influence public perceptions of a presidential candidate himself. It is one element of a diffuse public judgment on presidential leadership.
There is another consideration that is difficult for political scientists to quantify: the quality of vice presidential skills. This skill set is specific, peculiar and limited — like being the best carver of butter sculptures in the world. It involves relentless attacks on the opposing party's presidential nominee and effective advocacy of a policy agenda that isn't your own. It is simultaneously pit bull and lap dog.
I'm not sure anyone would be flattered by hearing, "You have such wonderful vice presidential skills." But they can be important. A presidential campaign is a series of messaging efforts, like drives in a football game. A vice presidential candidate can gain or lose ground.
By this standard, one Republican vice presidential prospect stands out. Chris Christie may have the aspect of William Howard Taft, but he has the manner of Teddy Roosevelt — tough, tenacious, tireless. Christie is naturally and constantly on the offensive. When he takes off his jacket at a town hall meeting, someone is in for a rough ride. But his most exceptional political skill is not confrontation but explanation — educating voters in the grim realities of state budgeting, public pensions, unfunded liabilities and teacher union obstructionism. He is both pugilist and professor — a good vice presidential combination.
Christie would not transform New Jersey into a presidential swing state — a persistent but hopeless Republican dream. But he could contribute to the repositioning of the Romney campaign in two important, seemingly contradictory ways. Christie would provide an infusion of blue-collar combativeness, which is foreign to Romney and pleasing to GOP conservatives. At the same time, Christie would represent a move to the ideological center. He is not a global warming skeptic. He supported an assault weapons ban in his state. He is an immigration moderate and has friendly relations with New Jersey's Muslim community.
Christie, at his worst, is capable of nastiness and name-calling — tendencies he would need to keep in check on a national ticket. But who else in the Republican Party combines a tea party tone with a relatively moderate public record? What other choice would cause Republicans to pray for 10 vice presidential debates?
Everyone on Romney's short list of prospective running mates is impressive. But Christie has the skills of a vice president.
Michael Gerson's email address is firstname.lastname@example.org.