MEXICO CITY -- Despite charges of widespread fraud, the opposition yesterday remained hopeful of winning an unprecedented two governorships in Mexico's midterm elections.
If the victories hold true, it would be only the second time in modern Mexican history that an opposition party had captured a state house.
Officials of Mexico's three major parties reported voter turnout in excess of 50 percent, especially in the hotly contested governors races in Guanajuato and San Luis Potosi states.
High voter turnout is considered key in overcoming the massive advantages of the Revolutionary Institutional Party, or PRI, which has lost only one gubernatorial election. That election was in 1989.
Many voters have been so disenchanted by the dominance of the PRI that some state elections have been decided by only 15 percent of the electorate.
In yesterday's election, the voters were to elect the 500-seat lower chamber of Congress, half the 64-seat Senate, six governorships and six state legislatures.
Though most attention has been focused on the governors' races in Guanajuato and San Luis Potosi, many political analysts believe that the makeup of the lower house of Congress will be of more historic importance.
If President Carlos Salinas de Gortari is able to recapture the two-thirds constitutional majority in the lower house, he will be able to make sweeping changes in the Constitution -- changes that will be needed for the forthcoming free trade agreement with the United States and Canada.
Among other things, the constitutional changes would permit foreign investment in oil and farming sectors.
But there was little indication yesterday that the reformed-minded president would be able to get the two-thirds majority the PRI lost in 1988, when Mr. Salinas was elected by the smallest margin in the history of the party.
While Mexico's economy has improved markedly since his election, the wages of ordinary workers have continued to slide in real terms, raising the possibility of opposition gains in this election.
The PRI was particularly vulnerable in Guanajuato state where Vicente Fox, a handsome former Coca-Cola executive and recent convert to the center-right National Action Party, or PAN, was challenging Ramon Aguirre, the PRI's gubernatorial candidate and a crony of former President Miguel de la Madrid.
Ramon Martin, Mr. Fox's campaign manager, yesterday predicted that Mr. Fox would win by 80,000 to100,000 votes.
Mr. Martin said that his prediction of a victory would hold true, even though the PRI-dominated election system had employed state policemen to intimidate voters and even though voting boxes were stolen in several pro-PAN areas.
Similar charges were lodged in San Luis Potosi state where Salvador Nava Martinez, backed by a three-party coalition, was seeking to win the governorship sought by the PRI's Fausto Zapata, another one-time associate of former Mexican president Luis Echeverria.
Jesus Gonzalez Schmal, a senior official of PAN, one of the parties supporting Mr. Nava Martinez, said that the ballot boxes for the governors race and even the ballots themselves never showed up at several communities.
A visit to a congressional election in District 83 in the capital revealed some illegal practices.
At two polling places, citizens were permitted to vote with just their plastic voter's card without their names appearing on the voters list.
Alfredo Cortina, the electoral institute spokesman, said that such a practice was a violation of Mexico's voting law.
"No one is allowed to vote unless he has the card and his name appears on the list," he said.
Martin Fernandez Flores, a pollwatcher in the 83rd District for the Popular Socialist Party, said: "This means that they [the PRI] could have issued hundreds of plastic voter cards and we would have no control over who these voters actually are."