Leftist Andres Manuel Lopez Obrador said his protests over alleged electoral fraud that have clogged Mexico City's center will transform into a long-term radical movement to change the nation.
The former Mexico City mayor, who claims electoral officials have tried to rig the July 2 presidential vote, told a crowd of about 5,000 supporters on Monday that his movement was just beginning.
"We are going to start a movement for the transformation of the nation's institutions," Lopez Obrador said. "We are going to transform our country and this is going to happen one way or the other."
The former Mexico City mayor has led a wave of protests to demand a vote by vote recount of the presidential election. An official count gave ruling party candidate Felipe Calderon an advantage of 0.6 percent, or about 240,000 votes, over Lopez Obrador.
The leftist candidate claims that a ballot-by-ballot recount would show he is the true winner.
On Monday, he lead a demonstration outside the Federal Electoral Tribunal, which ruled that it would only recount ballots at about 9 percent of the nation's 130,000 polling places, where it said there was evidence that the vote may have been miscounted.
Lopez Obrador wants the court to recount all of the 41 million votes cast and warned there would be consequences if it didn't agree.
"What is going to happen if they ratify this imposition?" he said in an angry, somewhat hoarse voice to his followers.
"Revolution!" his supporters replied with their fists in the air.
The court's seven judges are unlikely to be swayed. They voted unanimously for a partial recount that will begin today and last no longer than five days. They have until Sept. 6 to declare a president-elect or annul the race.
To press his case, leaders of parties supporting Lopez Obrador have called on protesters to follow Fox and demonstrate at every one of the president's public events.
On Monday, two Lopez Obrador supporters heckled President Vicente Fox, waving a banner that declared him a "traitor" as he spoke before a group of Indians in the state of Puebla.
Lopez Obrador has accused Fox, whose historic victory in 2000 ended 71 years of one-party rule, of using the presidency to ensure that his party won the election and called him a "traitor to democracy."
"Liberty of expression should be used responsibly," Fox replied to the hecklers. "Calling somebody a traitor is very serious. Nobody in this country should call somebody a traitor."
Supporters of Lopez Obrador have held a weeklong blockade of the capital's financial and cultural heart that is costing the city an estimated US$23 million a day in lost commerce and causing traffic jams throughout the city.
Although Lopez Obrador has urged the protesters to remain peaceful, many say they are ready for confrontation.
"We will carry on as far as possible," said protester Francisco Estrada, "until the people's will is fulfilled."
Representatives of Lopez Obrador's Democratic Revolution Party and Calderon's National Action Party will observe the partial recount, examining the markings on each ballot and challenging votes where they can.
The process could potentially swing the count in Lopez Obrador's favor. However, overcoming a 244,000-vote lead by re-examining just 9 percent of the ballots will be difficult.