Millions went to the polls in Afghanistan Thursday even while the Taliban upped its efforts to disrupt the country’s presidential election. Two Taliban insurgents were killed in a gun battle in Kabul, the capital, and rockets fell on some towns. The U.N. expressed optimism about the turnout. "The vast majority of polling stations have been able to open and have received voting materials," a spokesman said. Afghanistan's president Hamid Karzai faces an unexpected challenge from former foreign minister Abdullah Abdullah, with many predicting that a run-off may be necessary to determine the winner. A Kabul student told Reuters that the violence would not keep voters away: "The Afghan people are used to living under the worst circumstances of insecurity and fighting, why should they be afraid to come out and vote?"