MEXICO CITY (Reuters) August 28, 2006 — Mexico's top electoral court threw out leftists' allegations of massive fraud in last month's presidential election on Monday, handing almost certain victory to conservative candidate Felipe Calderon.

The seven judges voted unanimously to reject most of the legal complaints by left-wing candidate Andres Manuel Lopez Obrador, who said he was robbed of victory in the July 2 vote.

His supporters have paralyzed Mexico City with protests this month and he has vowed to make Mexico ungovernable if the court declares Calderon the winner of the country's most bitterly contested election in modern history.

The initial result showed Calderon, a former energy minister from the ruling National Action Party, won the election by just 0.58 of a percentage point or 244,000 votes,

The judges fell short of formally naming Calderon the winner but they said there were only marginal changes to the original results after recounts and annulments at some of the most fiercely contested polling stations.

"Based on the annulments that were deemed necessary, all the parties lost a considerable amount of votes but that did not affect the results,'' judge Jose Luna said.

The judges, whose rulings are final and can not be appealed, must declare a president-elect by September 6.

The Mexican peso firmed 0.85 percent to 10.88 per dollar as investors were convinced that pro-business Calderon will now take over from President Vicente Fox on December 1.

The election split Mexico between left and right and is the most serious challenge to its democracy since Fox's election victory six years ago ended seven decades of one-party rule.

Lopez Obrador says there were serious irregularities at more than half the polling stations. He has demanded a full recount of all 41 million votes cast and has launched street protests that have shut down central Mexico City.

If Calderon's victory is confirmed by the court, Lopez Obrador says he will either lead a civil resistance movement against his rival or set up some kind of parallel government.

"CORRUPT''

"The damned judges are corrupt. They are stealing the election from us,'' said Josefina Mondragon, 55, a housewife who was one of a small group of protesters outside the court.

The court annulled results from scores of polling stations after a partial recount earlier this month because of irregularities but there was no sign of huge fraud, the judges said.

"We can tell people that today their votes were worth something and that they are definitive,'' said another judge, Fernando Ojesto, adding that the court would in coming days rule on the election's validity and give a final vote count.

Lopez Obrador insists he won the election and that a court ruling in favor of Calderon would merely complete the fraud.

"It would be an abuse of the people's rights, a rupture of the constitutional order and a coup d'etat, which is offensive to millions of Mexicans,'' he told supporters on Sunday in Mexico City's central Zocalo square, where they have been camping overnight in a sit-in for almost a month.

But attendance at his mass rallies has dropped in the last two weeks and a campaign of blockading highways, government buildings and foreign banks appears to be losing steam.

Calderon, who campaigned on pro-business policies and would be an ally of the United States, was confident the court would declare him winner.

"We are sure that the only thing that will come out of these legal challenges is that Felipe Calderon won the presidency legitimately,'' said top aide Juan Camilo Mourino.

The leftist, who has vowed to overhaul economic policies to put the poor first, insists he will not give up. Some 50 supporters marched through the Zocalo with a fake coffin, marked "Democracy''

The electoral court this month ordered a recount at just 9 percent of the polling stations. It failed to end the dispute as Lopez Obrador says the exercise proved many ballot boxes were tampered with. He says almost 200,000 votes disappeared from some or were discovered in others.