Uruguay votes today in an election pitting a former rebel leader against a conservative ex-president in one of South America’s most stable economies. Opinion polls show Jose Mujica in the lead, but just short of an outright majority needed to avoid a second round. Mujica fought with the Tupamaros guerrillas in the 1960s and was jailed for years under Uruguay’s military dictatorship.Mujica’s main rival is Luis Lacalle, who was president himself in the early 1990s and who hopes to capitalise on voter resistance to figures from Uruguay’s militant past. Voters must also consider overturning a law granting amnesty from prosecution for human rights abuses committed during Uruguay’s 1973-85 dictatorship. In the run-up to today’s referendum, thousands took to the streets demanding the amnesty law be annulled. The demonstrations came a day after Uruguay’s Supreme Court ruled that the law is unconstitutional. It will be scrapped if more than 50 per cent of voters support its cancellation. The temperature has also been raised by the jailing last week of the former dictator Gregorio Alvarez. He was sentenced to 25 years in connection with the murders of 37 people kidnapped in Argentina in 1978. The victims were tortured at a secret detention centre before being taken back to Uruguay; their bodies were never found. Supporters of removing the amnesty law say they want to show that Uruguay is no longer paralysed by fear of its violent past.