MEXICO CITY (AP) March 13, 2006 — An opinion poll released Monday showed Mexico's leftist presidential candidate 10 points ahead of his closest rival, a day after local elections that saw strong gains for his party in Mexico's most populous state.

The poll, conducted by Mexico City newspaper El Universal, gave Andres Manuel Lopez Obrador, the former mayor of the capital, 42 percent of the vote. Felipe Calderon, a conservative candidate from President Vicente Fox's National Action Party, had 32 percent.

Roberto Madrazo, of the Institutional Revolutionary Party, or PRI, which ruled Mexico for most of the 20th century, was in third place with 24 percent.

The survey, which had a margin of error of 2.5 percentage points, was based on interviews with 1,500 registered voters from March 3-6.

Fox is prohibited by law from seeking re-election.

In Mexico state, home to 14 million people, Lopez Obrador's Democratic Revolution Party made substantial electoral gains in a region where it has traditionally been in third place.

With about 88 percent of the votes tallied from Sunday's balloting, the PRD had 31.3 percent of votes for the state's 75 legislative seats, barely trailing the long-dominant PRI, with 31.5 percent.

National Action fell into third place with 28.5 percent of the votes.