SANTIAGO: Chile's outgoing leftist President Michelle Bachelet predicted in elections Sunday that the race -- currently led by a conservative billionaire -- to pick her successor would go to a January 17 run-off.

"We all know there will be a second round, even though this first round is going to be very important," the immensely popular president said after casting her ballot.

Bachelet, who is barred from seeking reelection, is tipped to be replaced by Sebastian Pinera, a businessman with an estimated 1.2-billion-dollar fortune who owns one of Chile's four television networks, and has stakes in the national airline LAN and a football club.

If he wins, as polls suggest he might, he would break the 20-year-old grip on power by Bachelet's center-left Concertacion coalition which took over after the 1974-1990 military dictatorship of General Augusto Pinochet.

Pinera, 60, certainly exuded confidence as he voted in central Santiago for his second tilt at the four-year presidency.

"Better times are coming for those having it rough," he said, accompanied by his wife, one of his four children, and a dense pack of supporters and news media.

He boasted before the polls that the Concertacion coalition "is over... They exhausted themselves politically a long time ago."

Pinera's chief rival is Eduardo Frei, a 67-year-old former president who is Concertacion's pick.

But he trails well behind Pinera, partly because the left's support is fragmented.

A dark horse, independent and handsome former film director Marco Enriquez-Ominami, 36, has picked up backing from the part of the electorate tired of seeing the same faces in politics.

"I have a lot of confidence that the people will vote for a true change," he said as he voted in a town north of the capital.

Voter intention surveys conducted days before the election credit Pinera with 44 percent support, Frei with 31 percent, and Enriquez-Ominami with around 18 percent.

If no candidate picks up more than 50 percent of the ballots on Sunday, the run-off between the top two contenders would be held.

Sunday's elections will also renew the 120-seat Chamber of Deputies and 20 of the 38 members of the Senate.

Chile is a relatively prosperous nation that has largely weathered the financial crisis thanks to a "rainy day" state fund set up from revenues from copper, of which it is the biggest producer in the world.

Although unemployment has climbed to an uncomfortable 9.7 percent and the economy contracted this year, Bachelet is ending her mandate with a sky-high 80 percent popularity rating because of her careful economic stewardship that benefited the poor.

Whoever takes over is expected to continue much the same policies, although Pinera would face pressure from his conservative backers to roll back some of the government largesse.

Balloting on Sunday was due to end at 4:00 pm (1900 GMT), with first official results around three hours later.

There are 8.3 million registered voters in Chile, with a bias towards an older electorate because of apathy among the country's youth.

Voting was interrupted in a remote part of southern Chile when a group of indigenous Mapuche Indians blocked the road to demand the return of traditional land, according to officials quoted by the daily El Mercurio.

The group, wearing hoods, threw tree trunks and branches across the road in Pidima, 600 kilometers (400 miles) from the capital Santiago, said the region's governor, Jorge Saffirio