Known for brash statements aimed at other world leaders and rousing televised speeches, Chavez, 58, faced one of his toughest challenges against his opposition rival Henrique Capriles.
Yet Chavez was returned to the presidency in October 2012, capturing 54 per cent of the popular vote to win a fourth term in office.
Born in 1954, the second son of two school teachers in the village of Sabaneta, the young Chavez was interested in becoming a baseball star, not a politician.
He joined the military at 17, apparently in order to be moved to Caracas, Venezuela's capital, where he could be viewed by talent scouts.
Lacking major league skills, he ended up staying with the military and was deployed to fight a rag-tag rebel army. After hearing suspected rebels being tortured - allegedly beaten with baseball bats covered in wet cloths and speaking with his brother, a Marxist professor, Chavez apparently had an epiphany.
Hugo Chavez and his controversial quotes
"Don't mess with me, sir, or you will get stung."
- Addressing former Mexican President
"It would not be strange to hear that there had been
civilisation on Mars, but maybe capitalism arrived there
and finished off the planet."
- Comments on outer space, 2011
"The devil came here yesterday… it still smells of sulfur
- Addressing the UN General Assembly, referring to
former US President George W Bush
"Would it be so strange that they [the US] invented
technology to spread cancer and we won't know about
it for 50 years?"
-Blaming his cancer on possible US interference, 2011
He co-founded a group known as the Revolutionary Bolivarian Movement, named after Venezuela's independence hero Simon Bolivar, and began organising soldiers to take over the government.
"When he first came on the scene as this army officer… he seemed to be trying to forge a liberal approach between neoliberalism and Marxism," Kirk Hawkins, author of Venezuela's Chavismo and Populism in Comparative Perspective, told Al Jazeera. "His experiences over the past few years have led him down the Marxist road."
In 1992, during a period of repression known as El Caracazo under then president Carlos Andres Peres, Chavez, along with several army units, attempted to initiate a coup.
The coup failed miserably and Chavez was imprisoned. But he was allowed to address the nation on television for one minute before being taken away and took full responsibility for the failed operation. As most politicians blamed their problems on others, many Venezuelans saw his admission as inspiring and began organising for his release.
Chavez spent two years in prison before being pardoned in 1994 by then president Rafael Caldera.
He was elected president in 1998, promising to better distribute Venezuela's vast oil wealth to the poor, sparking a backlash from the country's former power brokers and beginning a period of intense polarisation.
"Chávez frequently refers to the bourgeoisie, the oligarchy and US imperialism," Sujatha Fernandes, professor of sociology at City University of New York, told Al Jazeera. "The opposition invokes the threat of communism and socialism, and scares the middle classes by saying that Chávez plans to expropriate private property.
"Each side creates labels and stereotypes about the other side, inflaming the situation."
Live Box 2012929152954771991
In 2002, following a bitter strike at the national oil company, the opposition attempted a coup. The plan, which saw Chavez shuttled off to a military base and his reforms rescinded, only lasted 47 hours.
The coup government, lacking any democratic legitimacy, was swiftly recognised by the US, further souring relations between the countries and leading Chavez to believe the US was conspiring against him.
After being reinstated, Chavez began clamping down on the private media, which - in some cases - provided intentionally distorted coverage of unrest in Caracas in order to help the opposition.
He pushed ahead with socialist-minded reforms, nationalising some industries, and increased his anti-US rhetoric. He called former President George W Bush "the devil" during an address to the UN and urged the world to read Noam Chomsky's book Hegemony or Survival, causing sales to skyrocket.
Despite his anti-US positions, the 2003 US invasion of Iraq turned out to be a boon for the populist leader, as it led to a massive spike in oil prices, and thus government revenue. "Oil rents create the unique possibility to undertake the project he is creating," Hawkins said.
He has provided oil to Cuba in exchange for doctors who work in poor areas of Venezuela, and has sent subsided petroleum to Latin American allies and even poor residents of the US. Critics accuse him of wasting oil wealth on foreigners at the expense of Venezuelans.
Poverty has decreased during his tenure, according to most studies. The United Nations Development Programme's Human Development Index, for example, which combines measures of income, health and educational attainment from 0 to 1, with higher levels of prosperity being closer to 1, has gone from 0.656 in 2000 to 0.735 in 2011, an increase of 1 per cent each year during Chavez's tenure.
Recently, Chavez has battled cancer in Cuba, and although he claims to have recovered, supporters worry about his health. Secrecy surrounding his physical state and the treatment itself have provided more fodder for the opposition.
In July 2012, Human Rights Watch accused the Chavez government of censoring the press and intimidating critics. "For years, President Chávez and his followers have been building a system in which the government has free rein to threaten and punish Venezuelans who interfere with their political agenda," the New York-based group said in a 133-page report.
"Today that system is firmly entrenched, and the risks for judges, journalists, and rights defenders are greater than they've ever been under Chávez."
Supporters of Chavez say the "Bolivarian Revolution" is under attack from unelected elites, backed by foreign powers, and that defending it is necessary.
"He wants to see great moral stakes in everything going on and to see himself as something very important," Hawkins said. "I am sure this is partly messianic, but plenty of other activists share that vision and way of framing things."
Gabriel Garcia Marquez, the Nobel Prize winning Colombian author, flew with Chavez before "El Commandante" first won the presidency. "I was struck by the impression that I had traveled and talked delightfully with two opposite men," Marquez wrote. "One who good luck had given the opportunity to save his nation -- and the other, an illusionist, who could go down in history as just another despot."
Source: Al Jazeera and agencies