Mexico has never seen anything like it - a presidential election so close that forecasts of rainstorms from state to state are being studied for their effect on the outcome.
Whoever wins Sunday's vote analysts agree that this election has already produced a more democratic and more plural Mexico.
Much of the credit for the change goes to maverick presidential candidate Vicente Fox. The cowboy from Quanajuato is largely responsible for ushering in a new, more-grass-roots campaign style in a country with a long record of inequitable electoral rules and political trickery.
"The rules of the game have changed because of the Fox campaign," says Federico Estevez, chairman of international studies at the Autonomous Technological Institute of Mexico in Mexico City. "Mexican politics are more open and mass-based because of him, and that can't be turned back easily."
The immense electoral machine that the ruling Institutional Revolutionary Party has built over 71 years in power gives some advantage to PRI candidate Francisco Labastida, a former governor.
"The coin's still in the air, although there is a better chance of the coin landing with the face of one candidate [Mr. Labastida] up," says Mr. Estevez.
The PRI's Labastida is battling political nonconformist Fox, candidate of a coalition of the center-right National Action Party and the tiny Green Party. Three-time presidential candidate Cuauhtmoc Crdenas trails in third place, but he has virtually no chance of Win or lose, Fox changed game winning, but could garner as much as a fifth of the opposition vote.
That's enough for advocates of a historic change in the presidential palace to label Mr. Crdenas the potential spoiler of their dream of a non-PRI presidency.
"There's never been such a competitive race in Mexican history with no one knowing who's going to win, and there's something beautiful about that," says Delal Baer, at the Center for Strategic and International Studies in Washington. "It sounds kind of democratic to me."
Sunday's election also renews Mexico's Congress, which most observers anticipate will remain divided among the PRI, PAN, and Mr. Crdenas's Party of the Democratic Revolution. Such a division would force the next president to develop a working relationship with more than his own party.
Developing a campaign more American in style than Mexican, Fox started his bid more than three years before election day. That was very different from the PRI tradition, which called for the president to handpick his candidate-successor several months before the vote.
Never a PAN insider - and recognizing that the center-right PAN would never be enough to carry a candidate to victory in a traditionally center-left Mexico - Fox formed "Friends of Fox," a nonpartisan political organization built around one candidate and designed to attract a wider support base than the PAN could.
With the Fox strategy showing signs of working in very early popularity polls - and with the ruling party already having lost its majority in Congress for the first time in 1997's midterm elections - PRI leaders knew they had to start changing their old ways, or perish. President Ernesto Zedillo announced he would give up the dedazo, or "big finger" the president used to pick the PRI's next presidential candidate.
Instead he called for the PRI to hold a national party primary, which took place last November. That resulted in some primary politics modeled on the Fox success - populist and detached from the central party bosses. The most notable example was the candidacy of PRI bad-boy Roberto Madrazo, who outshined Labastida in debates as Fox would later.
But the primary also gave the PRI a new claim to democratic legitimacy that provided its victor, Labastida, with a tremendous boost.
This is the first presidential campaign in which financing is essentially equitable. And as political analyst Estevez says, Fox has also played an important role in "forcing the mass media to open up and play fairer."
Media, especially television, have long been considered pro-government, and thus pro-PRI, giving the ruling party lopsided coverage. But Mexico's new Federal Elections Institute, overseeing presidential elections for the first time, tracks media coverage - and is finding it much more equitable than in the past.
Fox helped accomplish this, Estevez says, by "saying outrageous things very early on" which forced the media to take notice of him. For example, Fox seemed to lay claim to one of Mexico's most sacred symbols, the Virgin of Guadalupe, by parading with a banner of the Virgin's image.
"That kind of thing forced him into the media and made him recognizable," Estevez says, "although at a price." One of Fox's biggest liabilities is that voters tend to consider him contradictory with no guiding principles.
Despite that - or perhaps in part because of his sometimes outrageous comments - Fox has a base of fervent supporters that the gray Labastida, whom Zedillo calls "serene," doesn't have.
It is these supporters who could rain on Mexico's celebration of democracy if Fox ends up losing by a narrow margin. Despite signs of a PRI that is more prepared to play by the rules of the democratic game, a very narrow victory by Labastida would feed speculation about vote-buying and pressuring, and lead to charges that his victory is not legitimate.
"If the PRI wins with five percent or more" over Fox, "it won't be possible to question the result," says Mexico City political analyst Jos Antonio Crespo. "But if it's just 2 or 3 [percent], the lingering doubt will be that once again an election wasn't clean and fair."
Mr. Crespo notes that 7 million of Mexico's 15 million campesinos are poor enough to receive assistance from the government's "Progresa" program designed to address extreme poverty. If even a fraction of those recipients vote for the PRI because they fear losing the aid if they don't - that's enough to "leave people feeling the election was stolen again by the PRI."
Fully aware of that possibility, Fox unveiled an 11th-hour TV campaign: "Mexico, don't hold back!"
(c) Copyright 2000. The Christian Science Publishing Society