Editor's note: The 2012 presidential race is John King's seventh campaign. With presumptive Republican candidate Mitt Romney set to pick his running mate in the coming days, CNN's chief national correspondent looks at those believed to be in the running to be his potential vice president. King profiled former Minnesota Gov. Tim Pawlenty on Wednesday and Ohio Sen. Rob Portman on Thursday. Scheduling conflicts prevented Wisconsin Congressman Paul Ryan from sitting down to an interview for this story.
WASHINGTON, DC (CNN) - For Paul Ryan, debating Joe Biden might feel like a bit of a demotion.
He has, after all, been at the center of the budget debate with President Barack Obama and the entire Democratic Party for several years now, including some memorable, direct exchanges with the president.FULL STORY