Kabul, Afghanistan ? Afghans packed polling stations on Saturday for a historic presidential election that was blemished when all 15 candidates opposing U.S.-backed interim President Hamid Karzai withdrew, charging the government and the U.N. with fraud and incompetence.

In the end, faulty ink — not Taliban bombs and bullets — threatened three years of painstaking progress toward democracy. The opposition candidates claimed the ink used to mark people’s thumbs rubbed off too easily, allowing for mass deception.

Electoral officials rejected opposition demands that voting be stopped at midday, saying it would rob millions of people of their first chance to directly decide their leader, and the joint U.N.-Afghan panel overseeing the election would rule later on the vote’s legitimacy.

Even if the vote is ultimately validated, Karzai’s ability to unite this nation, fight rampant warlordism and crush a lingering Taliban insurgency in this nation of an estimated 25 million people might be fatally compromised if his opponents refuse to accept the results and insist that his rule is illegitimate.

But on Saturday, Afghans who braved the threat of violence to cast ballots were just happy to vote.

“I am old, but this vote is not just for me. It is for my grandchildren,” said Nuzko, 58, a widow who stood in line at a Kabul voting station. Like many Afghans, she uses only one name. “I want Afghanistan to be secure and peaceful.”

The controversy nonetheless cast a pall over what had been a joyous day in Afghanistan. Millions of ethnically diverse Afghan voters crammed polling stations for an election aimed at bringing peace and prosperity to a country nearly ruined by more than two decades of war. Men and women voted at separate booths in keeping with this nation’s conservative Islamic leanings.

Karzai — who is widely favored to win — said the fate of the balloting was with electoral panel, but he added that, in his view, “the election was free and fair … it is very legitimate.”

“Who is more important, these 15 candidates, or the millions of people who turned out today to vote?” Karzai said. “Both myself and all these 15 candidates should respect our people — because in the dust and snow and rain, they waited for hours and hours to vote.”

Afghan men stand in lines to vote at the main mosque in Herat, Afghanistan. Saturday's election, the first ever in Afghanistan, was called into question when the 15 presidential challengers to Hamid Karzai decided to boycott the outcome.

Taliban rebels got into a skirmish with U.S. troops that left at least 25 insurgents dead, and managed to kill three Afghan policemen accompanying ballots back to a counting center after the vote. Eight more police and two civilians died when their vehicles ran over mines.

But the rebels did not muster anything approaching the massive attack they had threatened to derail the election.

The boycott was a blow to the international community, which spent almost $200 million staging the vote. At least 12 election workers, and dozens of Afghan security forces, died in the past few months as the nation geared up for the vote.

Afghan women wearing burqas line up to vote at a polling station in Kabul. Afghanistan voters went to the polls Saturday in the country's first-ever direct presidential elections.

Uzbek candidate Abdul Satar Sirat, a former aide to Afghanistan’s last king and a minor candidate expected to poll in the low single-digits, said all 15 challengers to Karzai agreed to the boycott.

“Today’s election is not a legitimate election. It should be stopped and we don’t recognize the results,” Sirat said. “This vote is a fraud and any government formed from it is illegitimate.”

Islamic poet Abdul Latif Padran, another minor candidate, said, “Today was a very black day. Today was the occupation of Afghanistan by America through elections.”