So far this week, we've looked at why Dick Gephardt and Joe Lieberman can't get their presidential campaigns off the ground. Let's do something different, and see how high-flyer Howard Dean could crash and burn.

In almost every nominating race, one candidate surges strong early, gets all the adoring media, poses a surprising challenge to the front-runner, and then self-destructs. In 1980, we had Ted Kennedy. What killed Ted? Two things: Chappaquiddick and failure to ask an important question. The question was, "Why do you want to be President?" Kennedy's answer was an incoherent jumble.

Oops. But that was a small oops, compared to our other flame-outs.

That brings us to Gary Hart. Hart didn't quite crash in the 1984 race. It's just that, like Bob Dole in 1996, '84 was Walter Mondale's year. He was old, he'd been around longer than anyone else, and, uh, he was old and had been around longer than anyone else. So he got the nod. But Hart did well enough that 1988 should have been his year.

Then he got caught with a bikini girl on his lap in a yacht called Monkey Business, and we got stuck with Mike Dukakis. I'd say that's the sort of spectacular idiocy you only ever see on TV, except that TV is where you saw it.

Four years later and another wide-open race for the chance to run against popular war President George H. W. Bush. Mario Cuomo and Gephardt both bowed out when Bush's poll numbers were at record highs. Almost no one of any stature was willing to run. And so Bill Clinton looked likely to take it all – and did. But he almost Harted out. You remember the bimbo revelations, I'm sure. But the public (and more importantly, the press) was in a much more forgiving mood than in '88. That and Clinton's damage-control team was the best ever yet assembled.

But he was this close to going back to Arkansas, forever.

In 2000, Bill Bradley was the little train that couldn't. Sure, Bradley didn't go down in a blaze of crap like his forerunners, but he was the closest thing to a rock star in that sad little two-man race. It's just that the Gore machine had the money and the connections, and eventually steam-rolled over Bradley's Big Mo'. Like Mondale before, '00 was simply Gore's year, and no amount of momentum was likely to stop him.

This time around, we don't have a Mondale or a Gore. There's no Democrat in the White House, and there's no sitting vice president whose turn has come. This race is a free-for-all unlike anything we've seen since 1992.

Right now, Dr. Dean is the man with the Big Mo'. Dean knows how to work a crowd, he's got that whole angry populist thang, his people are creative and tech-savvy when it comes to getting voters excited and, more importantly, when it comes to raising money. In 1964, Barry Goldwater pioneered direct-mailing to raise money, and the Republicans have been masters of it ever since. Today, Dean is using the internet, and using it in ways no other Presidential candidate has before. Excitement, money, organization. Dean's got'em all, and they're the keys to victory.

But that doesn't mean he's going to win. The good doctor could still screw up.

Could there be bimbo eruptions boiling beneath the surface? Doubtful – he just doesn't seem the type.

Could this be John Kerry's year? Unlikely – his party power base isn't that big.

Could Dean fumble the "Why do you want to be President?" question? Not a chance – if you've heard the guy speak, you know he's on a mission.

So how could he fail? Simple: Howard Dean has got a great big mouth, and, like most populists, he doesn't know when to stop it from flapping.

A while back, you might remember Dean publicly musing about the day when America is sucking hind tit to China. OK, he didn't put it that badly, but he did say that the US "won't always have the strongest military." One job the President has, especially now, is to make sure that never, ever happens.

There's also this, from the Dean 2004 blog:

In the mess hall, Dean has what one might call a gaffe when he goes up to an African-American recruit and says, "you're not from Vermont, are you?"

That bit of non-PC talk isn't going to play well among black voters, and if the race stays tight, you can bet Gephardt, Lieberman, or Kerry will be Willie Horton-ing Dean for it.

And then there's this, showing Dean isn't just gaffe-prone, he's also thin-skinned:

[Dean] blasted possible war with Iraq as "unilateral," as he did in a speech at the DNC winter meeting two weeks ago.

[Meet the Press] Host Tim Russert promptly corrected him, noting 20-plus countries are backing the U.S.-led effort.

Well, okay, maybe it's not 'Unilateral,' he concedes, then blames a newspaper columnist for the gaffe.

If Dean wants to win, he's got to learn how to take it like he dishes it out – and he's going to have to learn to dish it out less often, in smaller servings.