John Kerry has thus far been seen as electable
John Kerry says he has learnt from Al Gore's failure to win the White House.
President Clinton's vice-president lost, John Kerry tells journalists, because people thought he didn't believe in anything.
That is interesting because people are beginning to think exactly the same about John Kerry.
Last year Democrats flocked to Howard Dean.
They were fired up by his fresh face, his straight talk and his positions, but in the end it was too much red meat.
American voters like change in increments, not revolutions. So they turned to John Kerry, not because they love him - though they may grow to - but because they are projecting their deepest wishes onto him.
The Democrats's dearest wish is to expel President Bush from the White House and at the moment they think Senator Kerry is the person most likely to do that.
Exit polls from Tuesday's primaries show that the main reason people voted for Mr Kerry was his electability.
In Missouri, 78% of the voters said that.
But the same exit polls show that electability is not the most important quality people seek in a candidate.
The main thing they look for is "a candidate who cares about people like me", the second is "a candidate who stands up for what he believes".
And in these areas, John Kerry did not score so well.
That suggests that
Who does that remind you of? Al Gore.
he doesn't relate well to voters
voters are not sure what he stands for.
Voters often sense these kinds of things before they know them as a fact.
But the facts would seem to show that this is a problem for Kerry.
During two decades in the Senate, John Kerry has successfully sponsored only nine laws.
And six of these nine are largely ceremonial.
John Kerry is married to Teresa Heinz Kerry
That is not what you call a major legislative legacy. He says he prefers to work behind the scenes rather than to blow his own trumpet.
Looking at his voting record, it is difficult to see where he stands politically.
He voted for the Patriot Act, the No Child Left Behind Act and of course, the War in Iraq - all flagship Republican initiatives.
Yet he supports gun control and gay rights and opposes the death penalty.
In American political terms, it is difficult to say whether he is left or right.
His supporters say this points to a man who makes up his mind on the issues, not on party ideology.
His critics say it smacks of political opportunism.
"John Kerry never met a side of an issue he didn't like," Jay Carson, a spokesman for Howard Dean, told Time.
John Kerry knows this is a potential bear trap for him, which is why he barely talks about his 19 years in the Senate.
Instead, there is a lot more talk about his four years in Vietnam.
That is not just political calculation - OK, it is, but it is not only that.
Kerry comes alive talking about Vietnam.
I've watched him on the stump and when Vietnam comes up, he steps out of his grey senatorial shell and becomes a full-blooded human being.
I asked him once why he travelled around with so many Vietnam veterans in tow.
Was he not worried that the sight of all these middle-aged men might not exactly appeal to the youth vote?
He was completely nonplussed by the question. "But these are my friends," he said looking a little hurt.
For John Kerry, Vietnam is much more than just a distant war.
It is becoming his way of connecting with voters.
Not only does it demonstrate that he is a leader in battle, it shows that he can relate to people of all creeds, colours and classes.
Mr Kerry needs to find a signature issue to define himself by.
If he doesn't, the Republicans will do it for him and it won't look pretty.
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