Mexico's most popular politician prepared on Friday to go to jail, after Congress ruled he should be tried for a minor crime that might end his presidential ambitions and create political chaos. Mexico City Mayor Andres Manuel Lopez Obrador, who polls show is the clear favorite to replace President Vicente Fox at 2006 elections, sat at home waiting for the ax to fall. "What happens now is that the attorney-general's office asks a judge for an arrest order and at that moment I go to jail," he told journalists outside his house. The mayor, an austere former Indian rights activist, has called for peaceful "civil resistance" to overturn legal efforts by the two main parties in Congress to knock him out of the presidential race. Despite this call, the case is likely to cause months of political turmoil. His leftist Party of the Democratic Revolution will likely organize mass street rallies, disrupt Congress and foment conflict between the federal government and local authorities it controls. --More 2323 Local Time 2023 GMT