WASHINGTON – Presidential candidate John Kerry on Tuesday chose former rival John Edwards as his running mate, selecting the smooth-talking Southern populist over more seasoned politicians in hopes of injecting vigor and small-town appeal into the Democratic ticket.

“I trust that met with your approval,” Kerry told a boisterous crowd of supporters in Pittsburgh who shouted their consent while waving hot-off-the-presses “Kerry-Edwards” placards.

The two senators – Kerry of Massachusetts and Edwards of North Carolina – sealed their political marriage during a 15-minute, early morning telephone conversation that papered over their differences in style and substance.

“I was humbled by his offer,” Edwards said in a statement, “and thrilled to accept it.”

Kerry, 60, a decorated Vietnam veteran whom critics call aloof, calculated that his ticket didn’t need foreign policy heft as much as a bit of pizazz and the quick embrace of party activists who had rallied behind Edwards’ stealth campaign for the No. 2 slot.

Edwards, 51, who made a fortune as a trial lawyer before jumping into politics in the 1990s as a self-styled champion for the common man, edged out several Washington veterans under consideration, including Rep. Dick Gephardt of Missouri and Sen. Bob Graham of Florida.

Along with Iowa Gov. Tom Vilsack, a veteran of state politics with a low national profile, they were finalists in a process that began four months ago with a list of about 25 candidates.

In March, after defeating Gephardt, Graham, Edwards and several others in the Democratic primaries, Kerry told his vice presidential search team to help him find a political soul mate who would be “ready at any minute” to assume the presidency.

Republicans on Tuesday questioned whether Edwards met either standard. While President Bush and Vice President Dick Cheney politely welcomed Edwards to a “spirited race,” their allies at the Republican National Committee issued a thick press release that called the first-term senator a politically inexperienced phony who is beholden to the trial-lawyer lobby.

“Disingenuous, unaccomplished liberal,” the RNC said.

Edwards’ relative lack of foreign policy work – he is a member of the Senate Intelligence Committee – could be an issue in a campaign shadowed by war, strategists in both parties said.

Privately, Bush advisers acknowledged that Edwards has the capacity to be a formidable foe, helping Kerry to broaden the electoral map and sharpen his economic message.

Edwards entered the Senate and public life in 1998 after upsetting Republican Sen. Lauch Faircloth. The son of a mill worker, Edwards worked his way through college sweeping floors before converting his law degree into a multimillion-dollar practice specializing in medical malpractice and product liability judgments.

He jumped early into a Democratic nomination fight filled with more seasoned politicians, including Kerry, who questioned Edwards’ decision to seek the presidency so early in his political career. In January, Kerry mocked Edwards’ lack of international or military experience.

“When I came back from Vietnam in 1969,” Kerry said, “I don’t know if John Edwards was out of diapers then.”

Mindful that Republicans will seize on the seasoning issue, Kerry assured supporters Tuesday, “John Edwards is ready for this job. He is ready for this job.”

Obsessed with secrecy, Kerry kept his decision to himself until the last possible minute, giving Edwards no time to get to Pittsburgh. The North Carolinian was at his Washington home, readying his children for summer camp, when he got word.

Democrats predicted the folksy Edwards will help the ticket in rural America, where Kerry’s patrician New England manner may not play as well. Democrats have lost enormous ground in the exurban and rural precincts, largely because of social issues such as abortions and gun control.

Edwards may also put his traditionally GOP state – and its 15 electoral votes – in play, along with other Southern venues, Democrats said.

During the primary campaign, Edwards did better than Kerry among Republicans and nearly as well among independents, according to exit polls conducted for The Associated Press by Edison Media Research and Mitofsky International. By comparison, among all voters in those primaries, Kerry beat Edwards 2-to-1.

Edwards portrayed himself as a positive campaigner, even as he criticized Kerry’s trade policies and mocked his long-winded style. Edwards scored political points with an anti-Bush message about “two Americas” – one for the privileged and another for everybody else.

Kerry, who has had trouble crafting a general election message, said of the new ticket, “I am determined that we reach out across party lines, that we speak to the heart of America, that we speak of hope and of optimism.”

Kerry’s choice was a bow to party pressure: Edwards was the overwhelming choice of delegates to the Democratic National Convention, according to an AP survey, and party leaders had been urging Kerry to shed his initial resistance to the senator.

Kerry and Edwards planned to meet for dinner with their families late Tuesday at Kerry’s Pittsburgh estate before launching a multistate campaign tour starting in Ohio on Wednesday and ending in Edwards’ home state Saturday.

They are the first senators to serve on the same ticket since 1972, when Democratic Sens. George McGovern of South Dakota and Thomas Eagleton of Missouri teamed up. Eagleton dropped out of the race because of his mental history.

A dozen years earlier, a Massachusetts senator with the initials JFK – John F. Kennedy – turned to a high-voltage Southerner he wasn’t particularly fond of: Sen. Lyndon B. Johnson of Texas.

Suggesting that Edwards was Kerry’s second choice, the Bush campaign rushed to the airwaves with an ad featuring Sen. John McCain, R-Ariz., who had rejected overtures from Kerry about a bipartisan ticket. In the spot, McCain praises Bush.

In Maine, Republican pollster Christian Potholm called the so-called “first choice” strategy “bizarre,” especially considering McCain publicly has never said Kerry offered him the job.

“It’s a little bit silly to think anybody would care that Kerry flirted with [McCain],” said Potholm, although crediting the Bush camp for stressing the alliance between the president and his popular primary rival in 2000. “[Kerry’s] not getting engaged and he’s not going to the dance with [McCain]. He’s going with Edwards.”

Jim Tobin, chairman of Bush’s New England campaign, congratulated Edwards on his selection, but ended the pleasantries there, leaving little doubt the GOP ticket would focus on his relative inexperience in government.

“I think that after a comparison of the records of Vice President Cheney and Senator Edwards, voters will see that [Cheney] has the experience needed to lead the country,” Tobin said.

While Maine Democrats did not want Edwards as their presidential candidate – the North Carolina senator finished fourth in the party’s statewide caucuses – they did like the idea of him as Kerry’s running mate.

Sean Mahoney, chairman of Edwards’ Maine campaign, said Edwards had the charisma and working class background to appeal to voters in the rural state.

“He’s somebody with the life experience who can relate to the people in Maine where jobs are disappearing,” Mahoney said of Edwards, the son of a mill worker and the first in his family to attend college.

Of Edwards’ lucrative trial lawyer background – something Republicans are sure to deride as the campaign progresses – Mahoney said it would serve him well in future debates with Vice President Dick Cheney.

“A lot of the cases he won were against people like Dick Cheney … people who underestimated him,” he said.

Praise also came from inside the State House with Gov. John Baldacci describing the Edwards-Kerry ticket as a “great one-two punch.”

Kerry’s team hurried out an ad featuring the newly minted ticket.

Kerry hopes the teaming dominates the political landscape during the three-week run-up to the Democratic National Convention in Boston.

Convention delegates will formally nominate the Kerry-Edwards ticket, whose common surnames were celebrated at the Pittsburgh rally with a rendition of Chuck Berry’s “Johnny B. Goode.”