EDITORIAL NEW DAY IN L.A. VILLARAIGOSA WILL NEED BROAD PUBLIC SUPPORT TO CHANGE CITY HALL.

AS Antonio Villaraigosa takes office today as the 41st mayor of Los Angeles, the eyes of the city and much of the world beyond watch.

Mayors, governors and public officials from across the country and hordes of media have all come to witness this historic moment.

This could be the dawning of a new era in L.A. and American politics.

We speak not about the much-hyped rise of Villaraigosa, the Latino politician. In a heartening testimony to the true diversity and colorblindness of L.A., ethnicity was largely a nonfactor in Villaraigosa's election. No, it wasn't identity politics that made Villaraigosa mayor. It was populism.

Antonio Villaraigosa was elected on the promise to shatter the corrupted, out-of-touch system of city politics. The promise to make voters and communities, not unions and developers, the focus of city government.

And if Villaraigosa is to deliver on the populist promise of his campaign, he will need the full support of the people of Los Angeles.

For decades, Los Angeles politics has been corrupted by special interests' feasting at the public trough. The fatter the interests grew, the worse the abuse. The culmination came in the administration of James Hahn, who, having spent a lifetime in city politics, knew how to milk the system to maximum advantage.

But Hahn played the game too well for his own good. His leadership delighted the well-connected, but outraged a usually apathetic public. Having attracted local and federal investigations, his administration ultimately repelled voters who yearn for leaders who will look after the public interest.

And so the public turned to Villaraigosa. Not just because he wasn't Hahn, but because he was everything Hahn wasn't - dynamic, energetic, charming; a man with the potential to challenge City Hall's prevailing powers, and not merely become one their tools.

All eyes have turned to Los Angeles today because of the hope that Villaraigosa will bring an end to politics as usual.

Unfortunately, hope isn't enough to save a political system mired in its corrupt ways. Nor, for that matter, is Villaraigosa's vigor or charisma.

Even today, as he travels from one inaugural event to another, Villaraigosa will find himself besieged by the special interests, many of whom gave generously to Hahn's campaign and seek to curry favor as friends of Villaraigosa.

Union bosses who fought him now swear their loyalty; contractors, developers and billionaires who weeks ago were his political enemies now put their arms around him and seek to continue their selfish games. City Council members who opposed him now offer flattery and fealty.

The task of orchestrating these insiders into a force for the good of the city can only be achieved if the public rallies to the cause.

No politician, no matter how well-intentioned, can overcome this entrenched power structure on his own. To defeat the insider culture, the reformer needs outside support.

The pressures Villaraigosa will face in City Hall must be offset by the pressure of the people - pressure for better, more responsive, more decentralized government.

That means the people of L.A. must organize their communities, get involved, stay informed and, when necessary, besiege their elected officials. It will take the vigilance of all Angelenos to give Villaraigosa the power to shake up L.A. City Hall.

Because as much as the people of L.A. need their new mayor, he will need them even more to lead the city to greatness.