Elections involve titanic efforts from tens of thousands of people, paid and unpaid, fueled by hope, optimism and patriotism -- and less admirable human qualities, like self-seeking and greed.

Whatever fueled Mexicans in their millions to attend massive rallies, talk and debate endlessly in coffee shops and curbside food stands, it has ended up in a near photo finish. During the day on Monday, Felipe Calderon of the PAN was ahead of Andres Manuel Lopez Obrador of the PRD by 400,000 votes out of some 40 million cast.

Understanding that grabbing the political high ground and looking strong is part of convincing the country you've won, both leading candidates took to the national airwaves in the hours after the polls closed and through the day on Monday to assert their right to become the next president of Mexico. All these brave declarations are based not on tabulated votes, what American political pros might call "hard count," but on dueling impressions of a raft of national exit polls.

What was missing in comparison to American elections was a running tab through the night, of what states of Mexico's 31 and the Federal District had reported, and what shares of the tabulated votes were going to which candidates.

The independent electoral commission, the IFE, had planned a transparent, squeaky clean, and non-controversial election night. At 8 p.m. Mexico City time, when the polls in the western part of the country closed, the commission would announce what its own nationwide exit polling had established, and declare a winner pending final tabulations.

Failing that, the IFE would have a preliminary winner at 11p.m.

Reality let the IFE down.

First, its own exit polling produced numbers so close it couldn't safely make a call at eight… and by eleven it was clear there would be no results to announce to the nation until Wednesday. When the head of the electoral commission made that announcement, I was standing in Mexico City's rainy central square, the Zocalo, with thousands of supporters of Andres Manuel Lopez Obrador. Just a few minutes before, the leader of Lopez Obrador's party in Mexico City had announced that based on all the numbers the campaign had, Lopez Obrador would be the next president of Mexico. It was in the midst of that frothy feeling that the head of the IFE, his voice broadcast across the vast square via loudspeakers, let the air out of the Lopez Obrador balloon.

Talk about a buzz kill.

The IFE chief's voice stopped bouncing around the cobblestones and facades, and then, on the jumbotron, came the face and familiar raspy voice of their guy, the man they were standing in the rain to hear. He was beamed from across town, from the hotel where the national and international press had gathered for an announcement from the PRD. This was more like what they wanted to hear: Based on the majority of the national exit polls, Lopez Obrador said, we have a comfortable lead of half a million votes. We are going to win, he said. He added for good measure, we have already won.

Buzz restored.

A motorcycle escort took the candidate to the central square for his victory party in the midst of a highly uncertain victory. Meanwhile, his chief rival stuck with a more buttoned-down set of instincts. Instead of following his original plan to ride the streets of the capital in a flatbed truck, Felipe Calderon declared victory, and headed into closed-door meetings.

So there I was: A wet foreigner who had come to Mexico to report on the election of a new president, and now I wasn't sure what was going to happen. Luckily I was in good company with about 110 million Mexicans.

There in the Zocalo doubt was in very short supply. This prematurely silver-haired bantam rooster of a candidate raised his arms over his head, and was announced as the next president by his party's victorious candidate for governor of Mexico City, Marcelo Ebrard. (Don't be surprised if Ebrard is a future PRD candidate for president. He trounced his PAN and PRI opponents in the second-biggest election in the country.)

Andres Manuel Lopez Obrador, often called by the acronym AMLO, gave the speech of a man who was ahead by 400,000 votes, not behind by the same. He promised his supporters their votes would be counted, and then turned up the heat, raising the prospect that his victory might be stolen, and urging the crowd to make sure that did not happen.

Then the thousands sang the Mexican national anthem, fireworks exploded on the stage and in the skies overhead, and a huge crowd started making its way home in the rain. Perhaps they were leaving to the next day a full-scale think-through of what it all meant for AMLO, and for Mexico.

For his part, Felipe Calderon, whenever an open mic came near, gently insisted he was the next president, cited his persistent lead in the unofficial national count, and used conciliatory language. Both men made choices that told you something about who they are.

Early the next morning Lopez Obrador was making the rounds of the national TV and radio networks, pointing out to audiences that even the IFE's own exit polls had him the winner consistently throughout the day. It was interesting that the PRD's modest lead, and the percentage difference separating AMLO from Calderon and the PAN hardly changed at all from the time the polls opened on the Caribbean until they closed on the Pacific. Where, AMLO asked, are those other votes?

On Wednesday the IFE will present the first official count. These totals will represent the original tabulations from the voting stations across the country, bundled by state, and brought to electoral headquarters in Mexico City. There will be no attempt, at first, to check the accuracy of the numbers on the outside of the bundled ballot papers.

In those bundles of ballot papers from 31 states and the Federal District of Mexico City are some 700,000 ballots that were either judged nullified at the polling place, or judged to have no vote marked for president. That amount is larger than the distance that separated the two leaders with more than 98 per cent of the vote counted. Are there votes in there that should be counted? Lopez Obrador wants to know.

This is totally uncharted water for Mexico. After all, it was a one-party state from the late 1920s until the year 2000. What challenges may come will test laws that were drafted in the 1990s in response to a 1988 presidential race that was generally considered fraudulent. In order to avoid repeating that experience, new safeguards and new institutions were created, and they seem set to get their first test now.

There are no other offices on a presidential ballot paper. There were separate ballot papers and separate ballot boxes for the national congress, senate, and various governors' races. That, along with the fact that Mexico has a national voting system with the same ballot papers and methods across the country will help in any challenge or recount.

Mexico is hardly out of the woods yet. Just the fact that Lopez Obrador may have lost sent the Mexican stock market, called the bolsa, and the Mexican peso higher in Monday's trading. Two scenarios seem plausible at midweek: that many Mexicans will sense a return to the bad old days of the hand-picked presidents, seeing the hand of the country's elite making sure the first-ever left wing president was defeated; or… the fact that the institutional machinery is grinding along, without instability, panic, or chaos will bring new confidence that Mexico is now a normally functioning democracy. I heard plenty of evidence of both as I talked to people in the days since the polls closed.

In an interview on French television before Election Day, President Vicente Fox talked of eventually changing Mexican law to bring in a runoff, so that the eventual president takes office having received at least 50 percent of the vote. Fox himself took office with 42 percent, and said that minority victory left him short on the power he needed to push his country to new places.

Whether Calderon or Lopez Obrador wins, the new president will take office having gotten just 36 percent or so of the overall presidential vote. That might not cramp Calderon's style too terribly much. He was the candidate promising the electorate in effect a second Fox term. The new congress will have his PAN as the largest party.

For Lopez Obrador the future looks a little tougher if he manages to find the votes to eke out a victory. His PRD will be the second largest party in the congress, without the power necessary to make the kinds of sweeping changes the candidate promised during his three years of campaigning.

Whoever wins, a few big truths were illustrated by the race:

1) Mexico is divided north and south. With few exceptions, the PAN won everything north of Mexico City all the way to the U.S. border, and the PRD won everything to the south.

2) Mexico has two big national parties, and the PRI isn't either of them. It would have been hard to believe just a few short years ago that a PRI candidate for president would, could, finish a distant third with barely 20 percent of the vote without carrying a single state, or that the once all-powerful party could be the third largest in the congress.

Certainly the PRI has as much chance as any party in a democracy to figure out a new way of talking to voters, and a new way to frame the issues. When Canada's Liberals came charging back into power in the 1990s, they so thoroughly swept the party of government, the Conservatives, that this once-dominant party was reduced to four seats in the parliament. Today Conservatives are once again running the show.

But PRI candidate Roberto Madrazo's pitch was basically, we're not right-wingers, and we're not left-wingers. The voters proved immune to that appeal.

Several people told me during the reporting trip that Mexico is fundamentally a cautious and conservative country. We'll know soon whether the economic or social realities were enough to push the country out of the comfort zone and make Lopez Obrador president, or if that deep conservatism was enough to bring a steady, unflashy conservative to the job for the next six years.

The retabulation of numbers generated at the country's polling stations went on all day at 300 counting centers around the country, and as that process went on, Andres Manuel Lopez Obrador enjoyed his first public lead since Sunday night.

Stay tuned.

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