Chile election: Bachelet and Matthei fight in run-off
Polls will close at 18:00 local time (21:00
GMT)
Chileans are casting their votes in a
presidential run-off, with Michelle Bachelet widely expected to win.
The left-wing candidate faces Evelyn Matthei, a former minister in the governing centre-right coalition.
Ms Bachelet, who was president in 2006-10, won the first round last month, but failed to secure an outright majority.
The contenders are the daughters of air force generals, once friends, who found themselves on opposite sides when Gen Augusto Pinochet seized power in 1973.
'Radical' manifesto
Polls across Chile opened at 08:00 local time (11:00 GMT) and will close 10 hours later.
Evelyn Matthei was labour minister in Mr Pinera's
government A paediatrician by training, Ms Bachelet, 62, won 47% of the vote in the first round on 17 November. Ms Matthei secured 25%.
Everything suggests Ms Bachelet will comfortably win the run-off, the BBC's Gideon Long in Santiago reports.
She leads an alliance of her Socialist Party, Christian Democrats and Communists and has campaigned on policies designed to reduce the gap between rich and poor.
Chile is one of the richest countries in Latin America, but millions have staged protests over the past few years to push for a wider distribution of wealth and better education.
Ms Bachelet wants to increase taxes to offer free university education and reform political and economic structures dating from the dictatorship of Gen Pinochet, who ruled from 1973 to 1990.
Her manifesto this time is much more radical than before, our correspondent says.
Ms Bachelet was constitutionally barred from serving a second successive term but was very popular when she left office.
Ms Matthei entered the race after two candidates of the centre-right alliance resigned earlier this year - one for alleged financial irregularities, the other one after struggling with depression.
Evelyn Matthei, 60, has called for a continuation of the policies of outgoing President Sebastian Pinera, asserting that Chileans are "better off" now than when he came to power four years ago.
As children in the 1950s, the current rivals were neighbours and used to play together on the airbase where their fathers worked.
Evelyn Matthei's father, Fernando, rose through the ranks to run a military school.
Michelle Bachelet's father, Alberto, who was given a job in the Socialist administration overthrown by Gen Pinochet, died of a heart attack in 1974.
An investigation concluded that the 51-year-old general probably died of heart problems aggravated by torture at the military academy.
A judge ruled earlier this year that Gen Matthei had no knowledge of or involvement in the torture.
The lower house of congress and half the senate are also being elected.
