Mexico’s long-ruling Institutional Revolutionary Party ended its worst political year in six decades on a high note Monday - apparently holding on to the governorship in the key state of Michoacan and maintaining a narrow majority in five state legislatures.

But as official returns poured in from local elections in six states and Mexico City, millions of Mexican voters appeared to continue to turn against the state party, strengthen the nation’s conservative opposition and reject its political left.

Official tallies will not be complete until later this week. But with more than 60 percent of the vote counted in most places, the National Action Party (PAN) - now the nation’s second-largest - was headed for wins in more than a dozen mayoral races in major cities and was neck-and-neck for second place in the Michoacan gubernatorial poll.

That showing for the 56-year-old, center-right PAN appeared to bolster its strategy to build a national power base that can unseat the PRI from the presidency for the first time in 66 years in the year 2000.

The biggest loser in the tallies of Sunday’s vote, though - as many analysts had predicted - appeared to be the populist Democratic Revolution Party (PRD). It lagged a distant third in most key contests.