Lost amid the hype about Barack Obama’s presidential prospects, and the conventional wisdom that the Democrats’ 2008 nomination is Hillary Clinton’s for the asking, John Edwards has been overlooked.

But the former one-term senator from North Carolina, who was the party’s vice presidential candidate in 2004, is perhaps its best chance to win the White House.

Part of this is merely the accident of his birth. He was born in South Carolina and no Democrat has been elected president since 1960 who wasn’t a Southerner. And that is the case because of more than just the happenstance of history.

Democrats need some electoral votes in Dixie to avoid painting themselves into an uncomfortable corner. It is mathematically possible for them to win without carrying Southern states, but as a practical matter it is a very, very uphill undertaking. It will get even more difficult after the 2010 Census shifts additional electoral votes south and west.

Meanwhile, the northerners that the Democrats have been nominating for president have been unable to appeal to enough Southern voters, who are generally more conservative, to make the region competitive.

But the real reason that Edwards needs to be taken seriously is that he made a good first impression on the American people, especially among Democrats when he ran for the 2004 nomination.

A recent Des Moines Register poll of Democrats in Iowa, whose caucuses kick off the delegate-selection process, showed him ahead. Edwards finished second in the state’s caucuses in 2004.

Every three months, the Quinnipiac University Polling Institute does a national poll that asks Americans to rate their warmth of feeling on a 0-100 scale toward 20 political figures. A score of 100 is the best possible rating. It is aimed at getting a handle on the gut feelings that voters have about politicians.

After all, it is often the intangible quality of likeability that makes a politician. Ronald Reagan and Bill Clinton, the two most successful political figures of the past half-century, won the votes of millions who did not necessarily share their views but were wowed by their charm.

Among the potential 2008 Democratic candidates, Edwards ranked second with a 49.9 rating on the Quinnipiac scale. One in five Americans don’t know enough about him to form an opinion, which means his popularity has room to grow.

Sen. Barack Obama of Illinois had a 58.8 rating, but 41 percent of Americans don’t know enough about him to have an opinion. Although this too gives him even greater room to expand his appeal, the fact that he has just burst upon the national scene makes his popularity less solid than other figures who have been in the public eye longer.

And then there is Sen. Hillary Rodham Clinton of New York. Her 49 rating is not that much lower than Edwards, but only 1 percent of Americans don’t have an opinion of her.

Because it is much harder to change someone’s impression than make a good one the first time, her room for growth seems more limited than Edwards. And that gives him a strategic advantage.

In addition, Edwards is viewed through a less partisan lens than Sen. Clinton, which is a useful attribute for a candidate. She had a thermometer scale rating of 20.5 among Republicans, while Edwards’ among the GOP sample was 33.5. Now, Obama’s is 37.6 among Republicans, but again his figures appear influenced by his newness to the national political scene. Of course Edwards faces all sorts of potential obstacles – whether Americans agree with him on the issues and think he has the gravitas to sit in the Oval Office.

Sen. Clinton is clearly the odds-on favorite for the Democratic nomination if she runs. But Edwards enters the campaign with some attributes that make him worth watching.