After four election wins, Venezuelan President Hugo Chavez is on track to completing at least 20 years in power, and supporters such as street bookseller Cristina Tovar say they're glad to have him in charge.

Tovar has signed up to receive new public housing, and the government has installed brightly painted kiosks for her and other vendors. Nearby, the city's streets are still lined with campaign posters emblazoned with the president's image.

In a region where military dictators ruled by force for decades, millions of Latin Americans such as Tovar are backing a new crop of leaders extending their rule and dominating power through the ballot box.

Already the Western Hemisphere's longest-serving president, Chavez has helped lead the charge of incumbents who have secured constitutional changes and stayed on for multiple terms, overturning provisions that had barred or limited re-election. Chavez won the right to indefinite re-election through a 2009 referendum and earlier this month was elected to another six-year term.

"He deserves to win as many times as the people elect him," Tovar said. "I adore my president."

Ecuador's leader, Rafael Correa, is widely expected to seek a third term in February, which could extend his rule to 10 years, while presidents in Argentina, Bolivia, Brazil and Colombia have also won re-election since 2006.

Some critics are uneasy about the health of the democracies in which a single person can remain in office for a generation. Even Chavez's friend and ally, former Brazilian President Luiz Inacio Lula da Silva, publicly advised the Venezuelan leader last week that a fourth term ought to be enough.

Silva, who was hugely popular and served two terms before stepping down in 2010, said in an interview with the Argentine newspaper La Nacion that "Chavez should begin to prepare his succession." Silva said that in Brazil he forbade his political allies from seeking a constitutional amendment to give him a third term.

"If I had done it, I would have wanted a fourth term, and then a fifth," Silva said. "For democracy, alternation in power is a conquest of humanity, and that is why it should be maintained."

Increasingly, though, popular incumbents have appeared virtually unstoppable, despite controversy about their efforts to stay in power.

As countries have benefited from a decade of economic growth, many presidents have won the allegiance of the poor and the working class, which for some has translated into a kind of fanatic devotion often seen in the past century, when populist leaders such as Brazil's Getulio Vargas and Argentina's Gen. Juan Peron rode popular support to long years in presidential palaces.

Since 1985, 15 of 17 incumbent presidents in Latin America seeking re-election have won, said Javier Corrales, a political science professor at Amherst College in Massachusetts.

Only two incumbents have fallen short: Daniel Ortega in Nicaragua in 1990 and Hipolito Mejia in the Dominican Republic in 2004, both amid economic troubles. In Ortega's case, he returned to power in 2007 and won re-election last year, extending his total potential time in office to 15 years. Nicaragua's Supreme Court in 2009 effectively removed term limits.

"It seems that in Latin America all you really need to know to predict an election is, well, is the incumbent running for office?" Corrales said.

Experts say that record speaks volumes about both the advantages incumbents traditionally enjoy and also the strong powers that Latin American presidents wield in often-fragile democracies.

"The fact is that these presidencies tend to be really powerful offices, much more powerful than the U.S. presidency is, relative to the other actors out there," said John Carey, a professor of government at Dartmouth College in Hanover, New Hampshire. "And the prospects for being able to self-perpetuate by abusing the authorities of the office are really big, in particular manipulating the courts, manipulating the media and manipulating budgets."

After Chavez beat rival Henrique Capriles this month by 11 percentage points, his narrowest margin ever, opposition leaders accepted defeat but also complained of Chavez's heavy spending on public housing and other social programs before the vote.

Some say that with Chavez entrenched for another six-year term, Venezuela runs the risk of further concentrating powers in the president, especially with his allies controlling the legislative branch. Voters in 2007 had narrowly defeated Chavez-backed constitutional changes that included abolishing presidential term limits, only to approve indefinite re-election in another referendum two years later.

"It's really depressing," said Gabriela Montero, a renowned Venezuelan pianist who lives in the Boston area. "I think having so much power and having so much money ... Chavez has been in a position of incredible advantage."

Montero composed a piece last year called "ExPatria," saying it grew from feelings of losing her homeland. Reflecting on the result of this month's election, Montero pointed to the words of 19th century independence hero Simon Bolivar, the namesake of Chavez's Bolivarian Revolution movement, who once warned that "nothing is so dangerous as to permit a citizen to remain in power a long time."

For his part, Chavez has also been invoking Bolivar while pledging a renewed push for oil-exporting Venezuela to become a more equitable, socialist society.

"Socialism equals democracy, democracy equals socialism — the power of the people," Chavez said in a televised Cabinet meeting last week, saying he aims to create a "21st century socialist democracy."

The trend toward multi-term presidents in the past decade has been dominated by left-wing leaders but has also included conservative Alvaro Uribe in Colombia. He stepped down in 2010 after a court blocked a referendum on whether he could seek a third term.

Term limits have a long history in Latin America as a way to check presidential power, with many countries imposing strict limits after the fall of military or civilian dictators.

Peru became one of the first to loosen those limits in recent years under President Alberto Fujimori, who shut down Congress in 1992. His allies then drafted a constitution that allowed him to be re-elected twice — before he fled into exile amid a corruption scandal. Peru went on to bar re-election to two consecutive terms.

Since 1995, seven Latin American presidents have followed suit and won the right to re-election through constitutional changes, said Ignazio De Ferrari, a doctoral student in political science at the London School of Economics. Several countries such as Mexico, Honduras and Paraguay still permit only a single term for presidents.

The latest fight over term limits is brewing in Bolivia as President Evo Morales gears up to run in 2014. Morales first won election in 2005 and then pushed for a new constitution in 2009 that allowed re-election. He now argues that the two-term limit began only with his 2009 win.

His opponents argue Morales is manipulating the rules, and the country's Constitutional Court has been called on to settle the dispute.

In many cases, Latin America's incumbent presidents have fared much better than incumbent parties that put forth a new candidate, giving leaders an incentive to loosen term limits.

As country after country follows suit, Corrales summed up his concerns in the subtitle of a recent research paper: "Can anyone stop the president?"


Associated Press writers Carlos Valdez in La Paz, Bolivia, and Gonzalo Solano in Quito, Ecuador, contributed to this report.


Ian James on Twitter: http://twitter.com/ianjamesap