The cartoonists haven't quite got a handle on him yet - but watch Howard Dean and a farmyard image comes irresistibly to mind: a spunky little bantam cock, the feathers on its chest puffed out to make him seem larger than he really is, positively spoiling for a fight with whatever other beast that should be so foolish.
Right now, Dean, all five foot nine of him, is living his first political apotheosis. True, not a single primary vote has yet been cast, but in the "invisible primary" of polls, fund-raising and buzz, Dean has been the runaway victor. History, moreover, suggests that, almost always, the candidate leading in money and popularity at this stage in proceedings will go on to win.
Tuesday's surprise endorsement from Al Gore may not change many minds, but it was the biggest prize of its kind going, proof that Dean has at least a foot in the door of a very wary Democratic Party establishment. There's just one problem.
Who exactly is Howard Dean? There is a surreal quality to the meteoric ascent of Dean to seemingly preordained nominee of his party to challenge George Bush in November 2004. His rivals are running on résumés - immense foreign policy sagacity, proven skill as a lawmaker, a glittering military career. Dean, however, is a man without a biography.
Yes, we know that for 10 years he was governor of a tiny New England state best known for Ben and Jerry's ice cream, superannuated hippies and same-sex civil union. But Dean makes little of his stewardship of Vermont - even of his success in balancing the budget and securing a measure of health insurance for virtually all the state's residents.
He has no international experience. On the "What did you do in the Vietnam war, Daddy?" question, Dean escaped the draft thanks to a bad back - not bad enough, however, to prevent him from spending the next few months skiing in Aspen, Colorado. We know he is a doctor (who met his wife Judith Steinberg when they both studied medicine in the Bronx).
She still practises today, and can give the impression of wishing he still did. "I just assumed [then] he wanted to be a doctor," she has said. "That's what we discussed."
In recent months, we have also learnt the sad story of his younger brother Charlie, who disappeared in Laos in 1974, never to be seen again. Just a month ago, his remains were discovered, and Dean flew to Hawaii to attend the ceremony marking their return. The tragedy marked him deeply; to this day, he wears Charlie's black leather belt. But no one knows exactly what happened. There have been suggestions, never proved, that the brother might have been executed as a CIA spy.
And Dean himself is a paradox. The insurgent who fires up crowds with tirades against the iniquities of the Bush administration is by background and breeding the Democratic challenger who most resembles fortunate George.
He is a native New Yorker whose father was a big shot on Wall Street (Dean as in Dean Witter). Like George W he attended Yale, where they overlapped for a year. They came from a similar East Coast Wasp background; Bush's grandmother was even a bridesmaid at the marriage of Dean's grandmother.
In Winning Back America, Dean's contribution to that miserable but mandatory literary category of candidates' autobiographies, he talks about his wealthy prep school and how he used to get drunk, before giving up alcohol after a riotous bachelor party.
"Let me get this straight," runs a joke by the late-night comedian Jay Leno that contains a barb of truth. "He had rich parents, drank a lot, went to prep school and avoided Vietnam. He's the alternative to George Bush? I think he is George Bush."
For good measure, Dean and Bush also have in common a rather unappealing smirk.
But there the similarities end. Bush junior decamped to Texas and threw in his lot with conservative Sunbelt Republicanism. Dean stayed in the North East, and became a Democrat. But, most important of all now, what sort of Democrat?
From one perspective, he seems the identikit liberal that he will undoubtedly be depicted as by Republicans should he win the nomination - the candidate who backs gay marriage, favours higher taxes and government-run health care, and trashes America's noble mission in Iraq. Look again, though, and Dean metamorphoses into a classic centrist, a fiscal conservative who hates budget deficits, supports the death penalty in certain cases, and opposes gun control. According to his website, he is "a common-sense moderate" - and the in-person Dean agrees. "It's pathetic that I'm considered the left-wing liberal. It just shows how far to the right this country has lurched."
In another sense also, Dean is not your average rabble rouser. He is not a great speaker. He tends to talk too fast, and monotonously to boot. He is pugnacious, but with none of Bill Clinton's supple charm. He's made little impact in the set-piece candidates' debates, and performed poorly in a now celebrated appearance last summer on Meet the Press, the most important of the Sunday talk- shows. Dean may be smart, but "his mouth moves even faster than his brain", says one critic, referring to Dean's propensity to fire off an answer which may be at odds with what he said the day before.
But his supporters love him. Not because of his impassioned support for balanced budgets, his vows to roll back the Bush tax cuts, and his progressive views on health care, or even because of his consistent, forthright opposition to the Iraq war. Dean owes his stunning success to two even more fundamental factors.
He "empowers" his audiences. "We can do better," he tells them. "This isn't about me. It's about you." Campaign workers are instructed to help as they think best, rather than be allotted menial tasks in a rigid organisation. The effect is magnetic.
But most appealing of all, Howard Dean takes the fight to George Bush. Democratic activists - the people who vote in primaries - loathe, literally loathe, George Bush and the hard-edged policies he pursues, despite "losing" the 2000 election. If Republicans whack Democrats, he'll whack 'em back.
Dean also has a terrific political nose. It is less well known that he toyed with a presidential run four years ago, and had to be persuaded out of the idea by Gore in person. He watched Gore's wooden, over-programmed campaign and instantly saw the disaster it was. Not by accident, Dean's 2004 effort is the polar opposite. John Kerry has gone the Gore route, of armies of advisers calibrating his every utterance. The result? A Dean lead of 30 points in the first primary state of New Hampshire, and a Kerry campaign facing meltdown.
But loosey-goosey, spontaneous politics has its limits. Much has been made of Dean's innovative use of the internet; the money he has raised through it, and its function as a 21st-century tom-tom drum, spreading the Dean message and Dean enthusiasm from neighbourhood to neighbourhood, from state to state.
But the Dean campaign is a child of the internet in another sense - rather shapeless, where everything is equal, and immediacy is everything. That approach has worked brilliantly in the insurgent, outsider phase of the campaign. But things have moved on. Dean is the favourite, the man to beat, the man with the money. No longer does campaign travel consist of a few seats on cut-price airlines; three chartered jets ferried reporters to Tuesday's campaign rally with Al Gore in Iowa.
No longer, too, can Dean continue as the man without a biography. Demands grow ever louder for the release of dozens of boxes of sealed documents relating to his five terms as Vermont Governor. If Dean is going to be the Democratic nominee, and possibly President, public curiosity about him will explode. The contents of those boxes may be completely innocuous. Sooner or later, though, they will be revealed.
The White House, we are told, is now starting to work on the assumption that Dean will be the Democratic nominee. The fearsome "opposition research department" of the Republican National Committee will get to work, digging up every dodgy Dean remark, sifting his record in Vermont and afterwards for the tiniest slips and contradictions.
The primaries won, Dean will scurry back towards the centre, and his stand on guns and balanced budgets gives him some leeway. Nor does he advocate a cut-and-run pullout from Iraq. But loose talk may come back to haunt him: his suggestion that Bush might have ignored specific prior warnings from the Saudis about 9/11, his throwaway line that "we shouldn't take sides in the Middle East", and his vows to raise taxes by repealing the recent Bush cuts.
All this would be more manageable if Dean came across as especially likeable. But there is a buttoned-down, harsh edge to him which may thrill true believers, but could alienate the non-committed in a general election. One lesson of recent American presidential elections is that the nicer guy (and the taller guy) tends to get elected. Think what you will of George Bush; if it had come to sharing a couple of (even non-alcoholic) beers with one of the 2,000 candidates, you would have chosen him over earnest Al Gore any day.
First, of course, Dean has to win the nomination, which will surely be settled by "Super Tuesday" on 2 March, when 11 states, including the mega-states of California, New York and Ohio, hold their primaries. But then the real struggle begins.
Democrats pray that Dean will be another Jimmy Carter, a little-known governor who won an outsider's victory in 1976. The spectre that haunts them is George McGovern four years earlier.
"Dean's campaign reminds me a lot of what we did 30 years ago," the former South Dakota Senator ruminated the other day. Democrats will shudder at the comparison. McGovern based his campaign on opposition to a war in Vietnam more unpopular than the one in Iraq. But he fell into the liberal trap and was obliterated by Richard Nixon in a landslide.
Born: 17 November 1948 in New York City, to Howard Brush Dean, a Wall Street investment banker and Andrea (Maitland) Dean.
Family: Married to Judith Steinberg whom he met at medical school. They have a son, Paul, and a daughter, Anne.
Education: BA, Yale University 1971. Albert Einstein College of Medicine, New York City.
Career: Physician in private practice, specialising in internal medicine, 1978-1991. Member of Vermont House of Representatives, 1983-86. Lieutenant governor of Vermont, 1986-1991. Governor of Vermont, 1991-2002.
He says: "You can't move people unless you stand for something. When I get done with this campaign, I don't know if I'm going to win or lose, but everybody in America will know what I stood for."
They say: "He was the only major candidate who made the correct judgement about the Iraq war. And he had the insight and the courage to say and do the right thing. And that's important." - Al Gore
"His English is incoherent, his reasoning shallow, his understanding weak. The amazing thing is that Democrats consider this guy the mental superior of George W Bush. Dean doesn't reach to Bush's knees." - James Taranto, The Wall Street JournalReuse content