Andrea Mitchell had a Democratic source telling her late Monday night that John Kerry would pick John Edwards as his running mate, but after a conference call with top NBC executives, she decided to hold off.

"The downside of being wrong was just too huge," Mitchell said.

After getting further confirmation, the veteran correspondent broke the story at 7:30 a.m. yesterday on "Today" and MSNBC -- and, unlike the New York Post, she had the virtue of being right. The New York tabloid, in a "Dewey Defeats Truman" moment, splashed on yesterday's front page a dramatic, unsourced, unbylined story declaring that Kerry "has chosen" Dick Gephardt.

Mitchell said she stayed up all night -- "I went home to change and bathe, in the interest of being collegial" -- and started bugging her sources again at 5 a.m. After getting a second confirmation, Mitchell reported at 7 a.m. that Kerry's running mate was "very likely" to be Edwards. By 7:30, following a conversation with a third source, she was reporting it as fact.

"This was pulling teeth," she said. "This was one of the hardest I've ever had to get. Some people I've known for decades wouldn't talk to me."

Fox News Channel's Carl Cameron, who has good relations with Democrats, reported the story 31/2 minutes later, and ABC's Linda Douglass about three minutes after that.

The story was especially hard to get, Cameron said, because "a number of Kerry staffers who were given the option of being involved opted out to protect themselves from screw-ups, to avoid a slip of the tongue with people they were living with in the bubble."

He said a Democratic source called him at 7:20 to say Kerry was about to call his choice -- the traditional way that word about such decisions leaks out -- and again minutes later to say it was the North Carolina senator. Kerry made the announcement at a Pittsburgh rally at 9 a.m.

ABC analyst George Stephanopoulos, who worked for Bill Clinton during his 1992 selection of Al Gore, said reporting was difficult this time because "Kerry was so determined to keep it secret that none of the usual suspects would say much."

While he believed that Edwards would get the nod, Stephanopoulos said, "you don't want to be wrong. You don't want to be the New York Post. Until the guy has made up his mind and is making the call, anything can happen."

How could the New York Post have rolled the dice, without even citing an anonymous source, on a story that had such great potential to backfire? Editor-in-Chief Col Allan, who made the decision, wasn't taking calls yesterday, saying in a statement through his publicist, Howard Rubenstein: "We unreservedly apologize to our readers for the mistake."

At the rival Daily News, executives sent the Post a case of cold duck champagne in mocking congratulations, and a bottle of Australian bubbly, inspired by Aussie editor Allan. In an editorial for today's editions, addressing Post owner Rupert Murdoch, the News says of Allan: "We beg you on bended knee to keep him in place. He's just too good, or bad, to be true. . . . So what if Allan has again made the Post a national laughingstock. Don't let any of that disturb you, Mr. Murdoch. Allan's prodigious pratfalls and capacity for flouting journalistic conventions are wonders to behold."

The Post's cover was selling for as much as $55 on eBay.

Does anyone outside the media business care who got the jump on a decision that Kerry was about to announce anyway? Probably not. But the networks compete intensely for bragging rights. "We're in the business of breaking news," said a sleepy Mitchell, who broke the news of Dan Quayle's selection by George H.W. Bush in 1988.

Coverage of the Edwards selection was generally upbeat yesterday, which is hardly surprising since some of the pundits had been openly rooting for Edwards and dismissing Gephardt as yesterday's news.

Edwards has "no shortage of charisma," said CBS anchor Harry Smith. CNN's Bill Schneider reminded viewers that Edwards is the "son of a millworker" who "clearly had a common touch," perhaps the party's best communicator since Bill Clinton.

The love affair has been brewing for some time. Back in the spring of 2001, Time anointed Edwards as "The Democrats' New Golden Boy," after People had pronounced him the nation's sexiest politician. The Chicago Sun-Times had said he "may well be the Democratic Party's best hope for 2004."

Edwards, of course, won only one state primary -- South Carolina -- but the final weeks of his campaign were marked by reporters pressing him at every stop on whether he'd agree to be Kerry's running mate. He routinely said he wasn't interested in the vice presidency, or that Kerry would make a good number two for him.

Not all the instant commentary yesterday was laudatory. There was talk about Edwards's trial-lawyer background and lack of foreign policy experience. ABC played a clip of Kerry saying that when he returned from Vietnam in 1969, "I'm not sure John Edwards was out of diapers then yet or not."

"The big question for John Edwards," the Wall Street Journal's John Harwood said on MSNBC, "is going to be answering the question, 'Is he ready to be president?' "

Fox commentator Dick Morris, a former Clinton strategist who has turned on his former boss, said Kerry's choice "is a real threat to Hillary" -- because after two terms Edwards would be well-positioned for an Oval Office run in 2012.

After all the pregame speculation, the choice was hardly a shocker. But by unveiling a relatively fresh face three weeks before the Democratic convention in Boston, Kerry and his strategists hope for a sustained period of high-energy coverage -- including the first pictures of the two men stumping together today.

"They stretched this out," Stephanopoulos said. "They built up the suspense. They want to own July. The vice presidential pick is filling a lot of the political space that used to be filled by the conventions, especially this year, when it looks like they will get less coverage."

Lost in the hullabaloo, but unearthed by the political newsletter Hotline, was a relatively obscure blog that got the scoop at 9:44 Monday night. A poster to noted that on Kerry's 757 in an airplane hangar, "John Edwards vp decals were being put on engine cowlings and upper fuselage."

NBC's Andrea Mitchell was the first to report that Kerry had tapped Edwards.The New York Post's "exclusive" turned into a huge embarrassment.