MONTEVIDEO : Ruling party candidate and former president Tabare Vazquez was favoured to reclaim the post in Uruguay’s run-off election Sunday, though groundbreaking marijuana laws in the country were facing an uncertain future. Uruguay’s first leftist president, Vazquez, 74, faces youthful centre-right challenger Luis Lacalle Pou, 41, a former president’s son and passionate surfer who appears to have lost steam heading into the final round of polling.

With heavy rain forecast for much of the country, voting began at 8:00 am (1000 GMT) to elect a successor to rabble-rousing President Jose Mujica. A result is expected early Monday. Mujica, famous for living in a run-down house and donating most of his salary to charity, remains popular but cannot stand for re-election under term limits barring presidents from serving more than five consecutive years.

Lacalle Pou, a lawyer, has run a muted campaign since the October 26 first-round vote, when he finished a distant second with 30.9 percent to 47.8 percent for Vazquez, a cancer doctor who kept up his practice while he was in office from 2005 to 2010.

Even the endorsement of third-place candidate Pedro Bordaberry, a fellow centre-right challenger who took 12.9 percent of the first-round vote, does not appear to be enough to salvage Lacalle Pou’s presidential dreams.

The most recent opinion polls give Vazquez between 52 and 55 percent of the vote, against 37 to 41 percent for Lacalle Pou.

“October’s results left very little chance, almost nonexistent,” said Rafael Pineiro, a political scientist at the Catholic University of Uruguay, sizing up Lacalle Pou’s chances.

Mujica, widely known by his nickname “Pepe,” is looking to hand power back to Vazquez, whose victory in 2004 represented a historic break with 174 years of dominance by the South American country’s two traditional parties: the “Colorados” (Reds) and “Blancos” (Whites, now officially called the National Party).

The ruling Broad Front (FA) party, a leftwing coalition founded in 1971, was banned under Uruguay’s 1973-1985 dictatorship and spent another two decades in opposition before finally coming to power.

Vazquez ran as the candidate of change when he won in 2004, cruising to victory in a single round as voters punished the two traditional parties for the region’s 2002 economic crisis.

He left office with a 60-percent approval rating after getting the economy back on track, passing tough anti-smoking legislation and launching a program to give every public school student a laptop.

The FA has now presided over 10 years of economic growth, which came in at 4.4 percent last year.

Vazquez, who has at times clashed with Mujica within the FA, cuts a much more sober figure than his successor, who still drives around in his beat-up Volkswagen Beetle and is known as “the world’s poorest president.”

Mujica legalized abortion, gay marriage and marijuana sales during his administration.

Vazquez has said his policy priorities will be education, infrastructure and security.

Mujica’s landmark initiative, legalizing marijuana, may face an uncertain future in Vazquez’s hands.

Under the law, the first of its kind in the world, marijuana users were supposed to be able to choose a supply source - pharmacies, cannabis clubs or home-grown plants - and buy or grow the drug in a regulated, fully legal market.

Vazquez has spoken out forcefully against smoking pot, called the idea of pharmacy sales “incredible” and said that if elected he would make “any corrections necessary” to the law.

Though the legislation officially came on the books in April, implementation is still in the embryonic stages.