Colombians are voting in congressional elections, with tensions high as rebels launch attacks in a bid to keep people away from the polls. A recent survey puts the conservative coalition behind President Alvaro Uribe close to an absolute majority, at least in the Senate.Colombia remains in the grip of a four-decade-long struggle between the Marxist FARC guerrillas, the government, and right-wing paramilitaries. The ballot results will give some indication of the support for President Uribe as he seeks re-election at the end of May. The latest surveys predict he will take around 48 per cent of the vote. He has gained popularity for cutting crime as part of his drive to stamp out the FARC rebel movement. The guerrillas’ response has been a show of force- killing eight soldiers and a policeman yesterday, and attacking civilians who defy their travel bans. Meanwhile the drug-gang dominated right-wing paramilitaries, who are officially demobilised, have been using intimidation tactics to manipulate voters.