MEXICO CITY — Top aides to leftist candidate Andres Manuel Lopez Obrador called Friday for a recount of nearly half the votes cast in Sunday's presidential election and edged close to demanding that the entire vote be nullified.
The statements by the Lopez Obrador camp revealed a two-part strategy to deny a victory to conservative Felipe Calderon, who on Thursday was proclaimed the winner by a margin of little more than half a percentage point.
By insisting on a recount of about 18 million of the 41 million votes cast, aides said, Lopez Obrador hopes to overcome Calderon's official 244,000-vote margin. The leftist has been insisting since Monday that there were widespread irregularities in the tally.
Simultaneously, Lopez Obrador's aides allege that President Vicente Fox improperly influenced the vote -- an accusation that could provide grounds for asking Mexico's electoral tribunal to nullify the election and order a new one.
Calderon is with Fox's National Action Party, and Lopez Obrador's allies have been arguing that the president's many TV and radio commercials touting his administration's successes were a thinly veiled attempt to aid his party's candidate. Mexican law does not allow the incumbent to intervene in the election of a successor.
Fox "violated the principles of equity, impartiality and objectivity," said Ricardo Monreal, a top official with the Lopez Obrador campaign.
Calderon, for his part, said he would prevail in any legal battle. If his victory stands, he will take office Dec. 1.
In a news conference with foreign correspondents, Calderon said he had won a "clear victory" supported by "the will of millions of Mexicans." He pointed out that many ballot boxes were reopened and recounted Wednesday during the preparation of the final vote tally. Those recounts, he said, found only "minor variations" from the election night tally.
"There is no valid legal argument that will lead to" an annulment of the election, Calderon said.
Mexico's electoral tribunal has overturned the results of several gubernatorial and mayoral elections in recent years, ordering new votes. In those cases, the losing candidates made charges similar to those against Fox: that leaders used their influence over local media and control of government coffers to violate the principle of "equity" in the competition among the candidates.
But legal experts said it was unclear whether the tribunal had the legal authority to void a presidential election.
