CARACAS, Venezuela — Hundreds of thousands of people flooded the streets of the capital Thursday to oppose a referendum that would eliminate term limits for President Hugo Chavez and help him establish a socialist state in Venezuela.

Blowing whistles, waving placards and shouting "Not like this!" the marchers carried Venezuelan flags and dressed in blue — the chosen color of the opposition — as they streamed along Bolivar Avenue.

"This is a movement by those of us who oppose a change to this country's way of life, because what (the referendum) aims to do is impose totalitarianism," said former lawmaker Elias Matta. "There can't be a communist Venezuela, and that's why our society is reacting this way."

The rally marked the close of the opposition's campaign against the proposed constitutional changes, which will be submitted to a vote Sunday. Chavez plans to lead rallies in favor of the reforms today.

Venezuelans will vote on 69 proposed changes to nation's 1999 constitution that would, among other things, eliminate presidential term limits, create forms of communal property and give greater power to the presidency.