Thousands of protesters caused commuter chaos on Monday (July 31) by closing off Mexico City's business district to traffic as they pressed the main leftist candidate's demand for a vote recount in a presidential election he says was stolen from him. Launching a campaign of civil disobedience that raises the stakes in Mexico's political crisis, Andres Manuel Lopez Obrador's supporters seized control of the capital's imposing Zocalo square on Sunday night (July 30). They also took over a six-mile (10-km) stretch of the elegant Reforma Boulevard, setting up their tents and huge tarpaulin covers in protest. The wide, tree-lined avenue is home to Mexico's stock market, many luxury hotels, government offices and headquarters of major corporations as well as the U.S. embassy. "We want the electoral process to be respected. We are not becoming violent in any way. The streets are blocked at times, but that is normal for protests," said Lopez Obrador supporter, Arturo Virreyes. The demonstrators did not close down buildings, allowing workers to enter their offices. But the occupation caused long delays for many commuters and some were furious. "It is necessary to defend the rights of the people and not these idiots," said commuter Edgar Juarez. "If this is what's happening now, imagine what will happen if he's president - he's illogical," added another commuter, Armando Santamaria. The Mexican peso fell 0.52 percent to 10.9160 to the dollar on Monday morning as investors became nervous about the protests. Lopez Obrador apologised to those who do not back his cause but said his campaign to overturn the July 2 election which he narrowly lost to conservative ruling party candidate Felipe Calderon would save Mexico's young democracy. It's unlikely that local police will step in to break up the protest movement as the police force is run by Lopez Obrador's Party of the Democratic Revolution. He was mayor until he stepped down last year to run for president. Calderon's margin of victory was just 244,000 votes, or less than 0.6 percentage points, and Lopez Obrador says results from more than half of polling stations were tampered with. The battle is now with Mexico's highest electoral court. Lopez Obrador is pushing for a full recount, while Calderon insists there was no fraud. The seven judges have to decide whether to reopen some or all of the ballot boxes by Aug. 31, which means Lopez Obrador's occupation of the capital could last for weeks.