Rob Portman, the ninja policymaker

Rob Portman has been around. Over the course of his career in public service, he has been appointed to positions in two presidential administrations. He has negotiated massive trade deals around the world and overseen the the process of crafting the president's multitrillion-dollar budget plan. He was a member of the House of Representatives for 12 years, is now a U.S. senator, and he just might become the next vice president of the United States. But hardly anyone knows his name.

In fact, a sizeable 62 percent of the population have "never heard of" Rob Portman and 15 percent have no opinion of him, leaving his nationwide approval rating at just 12 percent, according to a Gallup survey released Tuesday. The numbers reflect data from an ABC News-Washington Post poll conducted earlier this month where just over half of those surveyed said they had "no opinion" of Portman.

Florida Sen. Marco Rubio, also rumored to be a possible future running mate for Republican presidential candidate Mitt Romney, has twice the name recognition, according to the Gallup poll, which surveyed 1,012 adults May 10-13 and has a margin of error of plus or minus 4 percentage points.

Even in his home state of Ohio, Portman's name is a relative wild card. In fact, 59 percent of Ohio voters said they had not heard enough about Portman to have an opinion on him, according to a poll released last month by Quinnipiac University.

This is not to say that Portman is any different from VP contenders in past election cycles, many of whom were largely unheard of before their national profiles skyrocketed once they joined the ticket. Case in point: Sarah Palin was unknown to 71 percent of the country in August 2008, according to Gallup's numbers.

Which is to say, despite a long career of quiet service, Portman would finally become a household name if Mitt Romney taps him as his running mate.