A history of the vice presidents
In the more than 200 years since John Adams was sworn in, the office of vice president has evolved from a position of few responsibilities to one that is often integrally involved in major policy decisions. VP résumés vary greatly. But if presumptive GOP nominee Mitt Romney wins the White House in November, Rep. Paul Ryan of Wisconsin will join a long line of U.S. vice presidents who came to the office after spending time at the other end of Pennsylvania Avenue — in Congress. Read related article.