Rather than reinforcing Kerry's strongest traits, Edwards is likely to fill in certain perceived weaknesses, balancing out the ticket in a number of ways. Indeed, in some respects, the two men come across almost as opposites. Edwards's effortless style on the stump, which drew strong reviews during the primary campaign, stands in contrast to Kerry's stiffer delivery - and had Republicans Tuesday labeling the pick as Kerry's effort to fill in the "charm gap."
And while Edwards, like Kerry, is one of the richest men in the Senate, he comes from a far less elite background. Aides note that while the two men share many of the same values, they arrived at their beliefs through strikingly different circumstances.
"They both have a strong and deep understanding of the value of public service, but they come at it from very different backgrounds," says Steve Jarding, a former Edwards adviser. "Kerry learned it from his parents, traveling the world. Edwards [learned it] from a very different perspective. With far fewer means, he learned how to deal with the struggle of everyday life."
Edwards also injects a youthful flair - he is a decade younger than Kerry - and, as a senator still in his first term, more of an outside-the-Beltway perspective.
The biggest contrast of all, however, may be the fact that Edwards is a Southerner - something that will help give the ticket needed geographic balance.
Analysts say Edwards may not ultimately be able to deliver his home state, although it will certainly become more competitive now. But he could give Kerry a boost in more competitive Southern states such as Louisiana and Arkansas. And as a Southerner, he is likely to give the ticket a more moderate sheen, which could play well in Midwestern swing states.