A decade later, removing the PRI from power on the federal level remains the party's greatest accomplishment. Much of the center-right party's agenda has gone unfulfilled, and the PAN has largely failed to establish itself as a party of government -- despite having narrowly won the disputed 2006 presidential election.

The PAN faces voters again on July 4, as the country holds gubernatorial elections in 12 states. And while such races are largely influenced by local factors and regional political machines, the 2010 elections are expected to once again highlight popular disenchantment with a decade of PAN rule. It's also another chance for voters to pass judgment on the federal government's handling of the underperforming economy and the rampant drug-related violence that has claimed more than 23,000 lives since President Felipe Calderón took office in December 2006.

The polls don't favor the PAN in many of the 12 races. The PRI, which sells itself as a party that "knows how to govern," threatens to run the table, further extending its dominance of local-level politics and confirming its frontrunner status for the 2012 presidential elections.

The races also are expected to highlight internal shortcomings in the PAN itself. The party has suffered through four years of electoral losses at the local and national level, and discontent is rife over the meddling of the central party leadership -- headed by Calderón loyalists ­-- in local matters.

Some Panístas acknowledge their shortcomings and recent errors. But they also blame unfavorable circumstances -- such as the pervasive insecurity, the H1N1 outbreak and the world economic crisis -- for weakening the federal government and diminishing the party's short-term fortunes.

"Ours has been a government punished by circumstances," said former PAN deputy Gerardo Priego, who has been critical of the party's past handling of electoral matters. "Of course there have been errors, but circumstances haven't helped."

Local Weakness

PAN's victory in 2000 changed politics on the federal level, but state-level politics, where the party committed many of its biggest errors, continued largely unchanged. In some cases, it even changed for the worse, as PRI governors, who rule over a majority of Mexico's 31 states, took advantage of a weakened PRI central leadership to establish their own local fiefdoms.

The PAN also attempted to establish its fiefdoms, but its governors never displayed the political savvy of their PRI counterparts for courting and maintaining client groups and spending money in ways to ensure that their successors win office. In comparison, PRI governors heavily influence local nominations and often run the campaigns of their preferred successors.

The central PAN leadership, meanwhile, has meddled frequently in the candidate selection process, provoking charges that the party has abandoned its democratic principles for the PRI tactic of appointing preferred candidates through a practice known as "el dedazo," or the big finger.

National Weakness

The PAN has traditionally performed better on the national level, where it retained the presidency in 2006 and won pluralities in Congress. But strategic errors on the national level also hurt the party, beginning with its decision to work closely with the PRI after the controversial 2006 election -- a race many in the left-wing Democratic Revolution Party (PRD) still dispute.

With PRI support, the PAN achieved reforms to pensions, the judicial and electoral systems, and the petroleum sectors. But in return, the PRI extracted more federal money for its governors, and kept several controversial PRI governors from being sacked.

The PAN, Priego said, never properly reached out to the moderate PRD factions in an effort to lessen PAN dependence on the PRI for legislative support between 2006 and 2009. He called working too closely with the PRI and other controversial groups, such as the powerful and hardly transparent teachers' union, an error that tarnished the PAN's image.

Other observers cite the government's inability to champion major reforms and its straying from the original PAN principles of small-government conservatism and clean governance as mistakes, too.

"The right is supposedly in power. We don't see that in their policies," said Jeffrey Weldon, director of the political science department at the Autonomous Technological Institute of Mexico (ITAM). "We see them raising taxes all the time . . . [and not] trying to cut back on the size of government."

A PRI Return?

Even with the PAN's missteps and the PRI's resurgence on the local level and in the 2009 midterm elections, many political observers refuse to rule out the possibility of the PAN recovering and ultimately capturing a third presidential term. They point to recent history for telling examples.

The PRI performed strongly in the 2003 midterms and recaptured local governments in Northern Mexico at around the same time, but that didn't keep it from stumbling badly in the subsequent presidential elections.

And barely two years before the July 2006 elections, Calderón himself was a party insider and former energy secretary with a low public profile. He went on to pull an upset in the PAN primary elections, and then overcome an opponent with a wide lead in the presidential election.

Victories on the state and local levels often fail to translate into federal success. And some observers say the PRI has received little scrutiny, and has mainly benefitted from a lack of infighting and its opponents missteps.

"The PRI looks to be winning and winning big, but a lot of it may have to do with the fact that the both the PAN and the left have been employing losing strategies," said Federico Estévez, political science professor at ITAM.

"When you're looking at all that, the PRI looks great."

David Agren is a freelance journalist in Mexico City. He previously covered government and politics for The News, Mexico City's English-language daily.