0220 GMT December 18, 2017
He last held the top job from 2010 to 2014, euronews.com reported.
Opinion polls show Pinera with a commanding lead over his seven mostly left-of-center rivals, but still shy of the 50 percent needed for an outright win.
Leading the field trying to stop his return is former TV anchorman, Senator Alejandro Guillier. The center-left candidate has vowed to deepen the tax, labor and education reforms of his ally, outgoing President Michelle Bachelet.
Bachelet can’t run for office again because of term limits. She will step down with approval ratings near 30 percent and the legacy of her social and economic policies uncertain.
Pinera garnered international attention and domestic praise for his handling of the dramatic rescue of 33 trapped miners during his prior term in 2010, and is seen as a safe pair of hands by investors.
But his administration was marred by massive student protests seeking an education overhaul. His responses were often seen as out of touch and grassroots groups still oppose him.
Both Pinera and Guillier would keep in place the longstanding free-market economic model in one of Latin America’s most developed countries.
A key challenge will be getting people out to vote at all. Many are disenchanted with politics after campaign finance scandals that have tainted parties of both the right and left.
A strong showing of voters could help the left gather enough votes to defeat Pinera in an eventual December 17 second round, while apathy and continued quarrelling among left-leaning parties would pave the way for a Pinera victory.