Socialist Michelle Bachelet is set to become Chile's first woman president after winning Sunday's runoff election.

Her rightist opponent Sebastian Pinera conceded defeat as vote tallies put Bachelet ahead with 53 percent of the ballots.

Pinera was behind with less than 47 percent. Two-thirds of the vote have been counted.

Bachelet, a former political prisoner and later a defense minister, had been projected to win.

Succeeding current President Ricardo Lagos, she will inherit an economy that has surged in part because of soaring prices for copper, which is Chile's top export.

Some information for this report was provided by  AP and Reuters.