Officials with the Federal Electoral Institute (IFE) said the recount would not significantly change preliminary results of the presidential vote that showed Enrique Pena Nieto of the Institutional Revolutionary Party (PRI) winning with more than 38 percent of the vote, 6.5 points clear of his nearest rival.

Leftist runner-up Andres Manuel Lopez Obrador refused to concede and is demanding a new tally, alleging vote-buying and coercion by the PRI, whose seven decades of rule in the last century were marked by widespread allegations of vote-rigging.

Lopez Obrador had asked for a recount of every vote, but the IFE said on Wednesday just over half the polling booths for the presidential race met the necessary conditions set out by a 2007 electoral law.