MEXICO CITY Left-wing Mexican presidential candidate Andres Manuel Lopez Obrador moved up into second place in the latest poll from daily El Universal, but front-runner Enrique Pena Nieto continues to maintain a commanding lead.
With seven weeks to go until the July 1 election, Lopez Obrador, who nearly won the presidency in 2006, rose 2.9 percentage points to 24.8 percent, in the latest voter survey by polling firm Buendia & Laredo for newspaper El Universal. That followed other polls showing a similar rise.
Still, analysts doubt that Lopez Obrador will advance enough to threaten the lead of Pena Nieto, candidate of the opposition Institutional Revolutionary Party (PRI), who edged up half a percentage point to 49.6 percent in the same poll.
The left-wing Party of the Democratic Revolution (PRD) is strong in the country's capital, but weak in other parts of Mexico and Lopez Obrador lost widespread support after mounting protests when he contested his 2006 loss.
The PRI ran Mexico for 71 years until it was ousted in 2000 by the conservative National Action Party (PAN) of President Felipe Calderon. Mexican law bars presidents from serving more than one six-year term.
PAN candidate Josefina Vazquez Mota slipped 4.5 points to 23.1 percent in the latest poll.
The ruling party has lost support because it has failed to create enough jobs and contain drug-related violence that has killed 50,000 people since Calderon deployed the army to battle gangs upon taking office in 2006.
Vazquez Mota on Sunday accused Pena Nieto of a making a deal to win the votes of the country's powerful teachers' union.
Before the 2006 elections, teachers' union leader Elba Esther Gordillo broke with the PRI to back Calderon, giving him an edge in his narrow victory over Lopez Obrador.
VIOLENCE A FACTOR
A surge in recent violence could influence voter preferences. On Sunday, 49 headless bodies were dumped on a highway near Mexico's northern city of Monterrey in one of the country's worst atrocities in recent years.
Surveys show voters think that the PRI is more likely to quell the violence.
Its long rule was tainted by corruption and critics have accused the PRI of making deals with the drug cartels to maintain order.
The El Universal survey followed the first televised debate a week ago, where Lopez Obrador may have gained some ground with his attacks that painted Pena Nieto as a pawn of dominant broadcaster Televisa and a tool of corrupt PRI elder statesmen.
Newspaper Reforma reported on Friday that Pena Nieto had paid leading broadcasters to make favorable comments about his administration when he was governor of the state of Mexico, a populous region next to the capital, from 2005 to 2011.
Pena Nieto denied this, but Lopez Obrador seized on the reports to press his charges that the PRI hopeful is beholden to Televisa, which has been able to lobby against allowing more television broadcasters in Mexico.
Pena Nieto is the first PRI candidate in decades to enjoy the full support of his party's sprawling base that ranges from industrial unions to agricultural workers' organizations.
The latest El Universal poll was conducted May 7-10 and surveyed 1,000 eligible voters. It had a margin of error of 3.5 percentage points, the newspaper said.
(Reporting By Michael O'Boyle; Editing by Eric Walsh)