Chile's once and future leader Michelle Bachelet has won a presidential runoff, returning center-left parties to power by promising profound social changes in response to years of street protests.<br /><br />Bachelet won 62 percent of Sunday's vote, the most decisive victory in eight decades of Chilean elections.<br /><br />Evelyn Matthei, the presidential candidate of Chile's ruling conservative coalition, choked back tears as she conceded defeat, Al Jazeera's Lucia Newman, reporting from the capital Santiago said.
