Venezuelan President Hugo Chavez mounted a lavish celebration on Saturday to mark the 20th anniversary of the failed coup that helped launch his political career, as opposition leaders slammed the event as a blemish on the country's democracy.

The discord over the elaborate military parade that lionized the 1992 putsch is a reminder the OPEC member nation remains sharply divided over his leadership in the run-up to the October 7 presidential election.

We will not give rest to our bodies nor our souls until we have freed the country from backwardness ... and built socialism of the 21st century, Chavez said, echoing an oath he took in the 1980s with other leftist military conspirators.

Helicopters and Russian-made Sukhoi fighter jets flew overhead, and soldiers carrying weapons marched while shouting, February 4, socialist fatherland.

The former soldier was accompanied by allied presidents, including Cuba's Raul Castro and Bolivia's Evo Morales.

The failed coup made Chavez a household name in Venezuela, and paved the way for his 1998 election.

But his annual commemoration of the event has traditionally divided Venezuelans between supporters who say it honors the end of an era of corrupt politics and critics who call it a gratuitous celebration of violence.

The country's primary opposition coalition wrote a letter to the Organization of American States denouncing the event as anti-democratic.

The promotion of a coup d'etat contradicts democracy as an end and as a means because it celebrates military uprisings against constitutional order, the letter says.

COUP CELEBRATION

Chavez mocked the critics as a bourgeoisie that is lost without a map and without a compass.

Analysts and pollsters say Chavez is likely to win six more years in office thanks to liberal spending of oil revenues.

The opposition holds primaries on February 12 that will determine the challenger, with the youthful Henrique Capriles, governor of Miranda state, seen as the most likely candidate to face Chavez.

Reactions to the coup celebration in Caracas were predictably mixed on Saturday as the rumble of jets and helicopters served as a reminder across the city of the unfolding event.

For me, this is a day of death, for Chavez it's a day of celebration, said Jose Alfredo, 21, a student relaxing with a friend in a Caracas park. This is wrong.

Venezuelan Twitter users flooded the site with names of people killed during the uprising, with some tweets including the question: Is this what we are celebrating today?

The leftist leader's ideological crusade that demonizes the United States and looks to Cuba as a model has captivated the country's working classes, although his support is built most strongly on social spending funded by windfall oil revenue.

Government programs known as missions that provide benefits ranging from free health clinics and subsidized food to apartments and cheap financing helped Chavez win an overwhelming victory in his 2006 presidential bid and are seen tipping the balance in his favor this year.

In the neighborhood of 23 de Enero, a traditional bastion of Chavez support, residents feted the anniversary.

We had 40 years of repressive right-wing governments until Chavez arrived, said Miguel Pabon, 30, who runs a neighborhood community group. The fourth of February is the day that a true leader arrived, a leader who listens to the people.

(Writing by Brian Ellsworth; Editing by Peter Cooney)