Never let it be said that John Kerry rushes to judgment. Four months after just about every other Democrat had decided a Kerry-Edwards ticket was the best bet for the party, the presumptive Democratic presidential nominee has accepted the conventional wisdom and named North Carolina Senator John Edwards as his vice presidential running mate.

From that January night when Kerry and Edwards topped Howard Dean in the Iowa caucuses—effectively ending the Vermont governor’s chances of securing the Democratic nomination—there was talk about how Kerry and Edwards would be the best combination for the party. Kerry was always seen as the ticket topper. While Edwards was a better campaigner, Kerry had the organization and the money that would allow him to prevail in the primaries. And so he did. But as soon as Edwards folded his campaign in early March, after Kerry swept the Super Tuesday primaries, the question became: When are these two guys going to get together?

Why, then, did it take four months to close the deal? Why didn’t Kerry name his running mate in the spring, as some aides suggested he might, in order to mount a two-man challenge to the Bush-Cheney ticket during the critical months of late spring and early summer?

Kerry wasn’t ready, or willing, to embrace Edwards any sooner than he did. It was no secret that Kerry thought of Edwards as something of a hot dog, a first-term senator who entered politics as a mid-life career change and still seemed to be a bit better at delivering a stump speech than at sorting through the details of public policy. Kerry, a four-term senator, was more comfortable with another Washington insider, former House Minority Leader Dick Gephardt. But Gephardt inspired less enthusiasm than Kerry. Eventually, even Gephardt acknowledged as much; in a conversation several days ago, the Missourian quietly released Kerry to select Edwards.

The consistently cautious Kerry was never going to make a dangerous or unexpected choice. But he might well have picked someone other than Edwards—Gephardt, Iowa Governor Tom Vilsack or Florida Senator Bob Graham—if he had opened enough of a lead to look like a frontrunner. That never happened. With the election less than four months away, Kerry is, at best, running even with President Bush nationally and he is behind in a number of battleground states.

As the time to name a running mate approached, Kerry knew he needed to pump up the volume. And Edwards, who campaigned for the vice presidency more aggressively than anyone since Richard Nixon in 1952, made it clear to everyone that he was ready to give the Kerry campaign a charisma infusion.

It’s a given that Edwards adds star quality to the ticket. On paper, he’s a decade younger than Kerry; in person, he looks two decades younger. Edwards came out of the primary campaign with a reputation as the best candidate on the stump; in fact, several other candidates, including Dean and Al Sharpton, delivered better individual speeches, and Gephardt and Dennis Kucinich often scored more debating points. What distinguished Edwards was that his speeches were consistently solid and effective—and, as he began to speak more and more about the issue of poverty, the most moving—and his debate performances, while sometimes less than stellar, were never weak or embarrassing. What distinguished him even more was the skill with which he handled the press, and his genuineness as a one-on-one campaigner. Edwards wades into a crowd every bit as enthusiastically as Bill Clinton, and that’s going to count for a lot in the handshake-to-handshake combat that will characterize the campaigning in the battleground states that are likely to decide the fall race.

So what else does Edwards bring to the ticket:

• Consistency With Kerry: For better or worse, Kerry and Edwards are cut from the same ideological cloth, as their Senate records illustrate. Both men voted in 2002 to authorize Bush to invade Iraq, and then both men voted in 2003 against authorizing the expenditure of another $87 billion to pay for the occupation of that country. Both backed the Patriot Act. Edwards has a better record than Kerry on corporate issues, especially trade policy, but it is not dramatically better. Both men voted against impeaching Bill Clinton, against confirming John Ashcroft as attorney general, against the Bush administration’s tax cuts, against allowing development of the Arctic National Wildlife Refuge, against limits on abortion rights, and in favor of campaign finance reform, expansion of the Patients’ Bill of Rights and for most gay rights measures—for instance, though neither man advocates allowing same-sex marriages, they both oppose the proposed constitutional amendment to ban such unions.

• Southern Possibilities: Polls suggest that, while it’s an uphill struggle, Kerry could win as many as four southern states: Florida, Louisiana, Arkansas and North Carolina. Edwards, who makes a big deal about his southern accent, ought to be able to help in all of those states.

• Some Liberal/Left Appeal: Edwards is no lefty. His votes on the war and the Patriot Act disqualified him as a first-choice presidential contender in the eyes of Democrats who wanted to nominate someone who would battle Bush on those issues. But progressive activists have, from the start of the 2004 campaign cycle, tended to find Edwards more appealing than Kerry. In Iowa, Edwards and Dennis Kucinich worked out an agreement to support one another in caucuses where neither candidate was viable on his own—a deal that helped Edwards far more than it did Kucinich.

• A Real Challenger for Dick Cheney: In 2000, Democratic vice presidential candidate Joe Lieberman spent most of his time agreeing with Republican Cheney in their one debate. Lieberman’s failure to distinguish himself from Cheney hurt the ticket. That won’t happen with Edwards. Republican aides were already peddling the line that Cheney’s experience and gravitas will trump Edwards’ youth and enthusiasm. Don’t bet on it. Edwards shines in debates with Republicans—he beat a GOP incumbent to win his Senate seat in 1998. The North Carolina senator has been going after the vice president for months—he made a hit on Halliburton and war profiteering central to his stump speech during the primary season—and, as Kerry says, “I can’t tell you…how eager I am for the day this fall when he stands up for our vision and goes toe-to-toe with Dick Cheney.”

Above all, however, Edwards brings to the Kerry campaign something that has been missing up to this point: a recognizable and appealing domestic-policy message. With his talk about the need to close the economic gap between what he referred to as the “two Americas,” and with his emphasis on developing programs to aid the working poor, Edwards renewed old Democratic Party themes that will play very well—especially with wavering Democrats and independents—in a year when pessimism about the economy could yet decide the direction of the presidential race.

Now, only the most fundamental question remains: Will Kerry, who was never as comfortable with Edwards as he was with other potential running mates, be flexible enough to really incorporate Edwards, and the North Carolinian’s “two Americas” message, into the fabric of the campaign? If he does, he might yet prove one of the oldest American political cliches true: The vice presidential selection could be the most important choice of Kerry’s campaign.

John Nichols is the Washington correspondent for The Nation.