The Democratic Convention: Alongside the balloons, an air of realism - The Democrats meet in New York this week to endorse the man they are coming to believe can oust George Bush from the White House

THE PREPOSTEROUS, exhilarating hoopla is wonderful for morale. But what matters at this Democratic convention is unity. Five times out of the last six, the Democrats failed to conquer the White House. Whatever the song says, happy days will not return in 1992 - unless Bill Clinton can show his country he has created a party in his own image, at peace with itself and at one with him.

There may be scant sign of it on the streets of New York. Gays, the homeless and women's rights groups will be demonstrating, Aids victims will be marching - the very pressure groups that remind God-fearing, suburban America of everything it does not like about the Democrats. And all this in the city the rest of the country loves to hate.

Inside Madison Square Garden, however, if all goes according to plan, it will be very different. On display will be the new model party that Mr Clinton has spent his political career attempting to build: faithful to its liberal heritage, yet reshaped to reach out to the middle classes whose desertion in the 1980s proved fatal.

Bill Clinton has prepared the ground assiduously. By nailing down the nomination so early, he has been able to pack every committee that matters with his supporters. Few Democratic nominees presumptive have gone to their ritual crowning with such control of the convention agenda. In theory, the risk of bruising public floor fights is minimal.

The 9,000-word platform is the gospel of Clintonism. From its talk of a 'New Covenant' between people and government, promised on the day he declared last October, to the warm words for business, its emphasis on wealth creation rather than wealth distribution, and insistence on personal responsibility, the document embodies the centrist 'Third Way' for which the Arkansas Governor has long argued.

It urges defence cuts, but not such as to jeopardise US military supremacy and its capacity to 'use force decisively where necessary'. Only in its unconditional support for abortion does the platform have a liberal ring. It will be mighty hard for the Republicans to use the 'L-word' as they did so devastatingly against Michael Dukakis four years ago.

But the keynote will be unity. Nominating Mr Clinton will be none other than a once-suspicious Mario Cuomo, guardian of the party's New Deal soul. A deal has been struck with Paul Tsongas, his most serious primary opponent, whereby the former Massachusetts Senator will speak tomorrow night. In return, Tsongas-backers on the drafting committee voted to prevent the former Governor of California, Jerry Brown, from presenting his ideas in a full-scale debate.

Technically, Mr Brown's name may yet be placed in nomination. In effect, however, he has received an ultimatum: endorse Mr Clinton, support the platform and release his 600-odd committed delegates - or resign himself to presenting his quirky notions outside the convention.

Which leaves Jesse Jackson, who will speak tomorrow and who has crossed swords bitterly with Mr Clinton. But the Jackson bluff has been called. No longer is he the sole voice of the black community, and his influence at this convention is far less than in 1984 and 1988. On Saturday Mr Jackson bowed to the inevitable and tepidly endorsed Mr Clinton, gaining nothing in return.

In 1992, the master of the game is the moderate Democratic Leadership Council (DLC) which Mr Clinton once led. Nothing could be more symbolic than the choice of the Tennessee Senator Al Gore as running mate. Mr Clinton could have chosen a black, a woman, a north-eastern liberal, to 'balance the ticket'. The balance he has gone for is a man of his generation, from the same part of the country, cut from similar ideological cloth, another prime mover within the DLC. The message is plain: this is a different party, that wants to win.

The strategy has its dangers: Mr Jackson is down but not out. In eschewing him, Mr Clinton could forfeit his formidable campaigning ability to get out the black vote, a core Democratic constituency essential in a presidential year. Nor has Mr Clinton the coalition-builder dispelled the impression his party is in thrall to lobbies, Political Action Committees and other big contributors.

But that is a small concern. Democrats sense the tide is turning their way. No party has a greater talent for snatching defeat from the jaws of victory. But this time there is none of the giddy optimism of 1988 which caused defeat to be so painful. In 1992, alongside the hoopla, the balloons and the flagwaving, an unusual element is in the air: realism.