By 9 a.m, voters had formed long and peaceful lines under the watchful eyes of a heavy police and army guard to cast votes in rich and poor neighborhoods across Cairo. In several places, queues stretched as long as a block along the banks of the Nile, and there were similar reports from Alexandria and Port Said.
The Muslim Brotherhood, the group that defined Islamist politics, poised to win a dominant role in the Parliament of the country that for nearly six decades was the paradigmatic secular dictatorship of the Arab world.
But the prospect of that historic turn has been largely overshadowed here by another, more urgent contest unfolding outside the voting booths: between the military council that seized power at Mr. Mubarak's ouster and a resurgent protest movement demanding the council's exit.
The ruling generals have defied a week of protests to reiterate, more forcefully than ever in recent days, that they expect to yield almost no authority to the new Parliament, and might claim special permanent powers under the new constitution that the Parliament is to write. The council's top officer, Field Marshal Mohamed Hussein Tantawi, declared on Sunday that "the position of the armed forces will remain as it is - it will not change in any new constitution."
At the same time, the generals have set a political timetable calling for the Parliament to be seated in March and disbanded perhaps as early as July. They have established a convoluted and opaque voting system that is almost doomed to lack credibility. And nearly everyone expects widespread violence among supporters of rival candidates - a hallmark of past Egyptian elections and a preoccupation of pre-election commentary this time.
"The elections will have no legitimacy," said Sally Moore, a psychiatrist of Egyptian and Irish descent who was among the young organizers behind the original revolt against Mr. Mubarak.
"It won't be a working Parliament. It will be a Parliament that people want to overthrow," she said. "It is a sideshow. But it is being portrayed as a main event, because people want to have some hope. They will end up disappointed."
Many liberal candidates suspended their campaigns last week because of the protests. Several said they were urging their supporters to go to the polls on Monday just to limit the Islamists' gains, even at the risk of appearing to legitimize a questionable result.
"I expect a lot of violence," said Shady el-Ghazaly Harb, a liberal organizer who also took part in the original uprising. "But we are telling people to go and vote, because we don't want the Islamists to have the whole thing for themselves." The atmosphere, he said, was "very depressing."
A widely followed Facebook page that played a crucial role in rallying opposition to Mr. Mubarak captured the deep ambivalence of many of the original revolutionaries. It urged voters to go to the polls dressed in black, in part to mourn the more than 40 people killed last week in clashes with security forces during the protests against military rule.
"We want the elections to be the first white mark in the history of the revolution" but "a black mark on the front of the regime," the Facebook page, We Are All Khaled Said, declared. "We will go to the elections, because it is the first step on the path of taking power back from the military, who we think should go quickly back to their barracks."
In interviews, many Egyptians were already looking past the election, which will take place in stages over the next few months. Some said they feared its failure could give the military an excuse to keep power, perhaps under a reshuffled council.
But others argued that even a flawed election would lend the Parliament more legitimacy than street protesters could muster against the power of the military council, and the very act of voting would carry Egypt one step further from dictatorship and closer to democracy.
"This is a test, and the people have to take it," said Ali Khalifa, 55, a government worker who visited a cafe in Sayed Zeinab, a working-class area of Cairo. "But you don't take tests just to pass or fail. We can study for it and learn from it, because this is the first step in our future life."
The Muslim Brotherhood was about the only major faction in Egypt to withdraw from the protests against the military, or to assert that the election results could be credible.
That stance opened divisions in the Brotherhood, with some critics accusing it of selling out the cause of democracy for short-term political advantage.
"I wasn't comfortable with the Muslim Brotherhood's absence from Tahrir Square," Sheik Yusuf al-Qaradawi, one of the most popular Islamist thinkers in the region, said on state television. "Absence is not a correct position, in my opinion."
Still, in an interview Sunday night, Essam el-Erian, a leader of the group's new party, Freedom and Justice, put off any questions about the powers of the military or Parliament until after the election, for fear of unnerving voters.
"We are not going to have a debate with the military now," he said. "The battle will be after the election, if there is a need to battle."
The Brotherhood - once banned, but now Egypt's best-organized political force - faces competition from Islamic-oriented parties both to its right (founded by the ultraconservatives known as Salafis) and to its left (the Center Party and the Egyptian Current, each founded by moderate former Brotherhood members).
Among the liberals, there are two major coalitions. One, the Egyptian Bloc, is an anti-Islamist alliance of culturally liberal parties with economic policies ranging from business-friendly to state-run socialist. The other, the Revolution Continues Alliance, includes the Egyptian Current and a party founded by young leaders of the revolution. And there are many smaller parties and a profusion of 6,000 candidates for about 500 seats.
Election experts say Egypt's voting system seems almost designed to confuse. Each voter is expected to pick one party list of candidates and then two individual candidates, who may also be running on party lists. The individual candidates qualify in one of two categories, one as a worker or farmer, the other as a professional, following a decades-old rule that bedevils party recruitment. Candidates appearing on television over the weekend were unsure whether voters had to pick one from each category or could pick any two candidates.
"We are walking into a completely unknown scenario," said Kamel Saleh, a candidate from the new Social Democratic Party, who is running in central Cairo. "We should probably think of the scale of mismanagement as being intentional."
Nor do the polling procedures inspire confidence. With staggered rounds of voting by region, the first round extended to two days from one, the ballot-counting to be done at central locations rather than at polling places, and final results to be withheld from the public for weeks, there was at least the appearance of much opportunity for manipulation.
All told, the staggered rounds and possible runoffs mean that Egyptians may be voting on as many as a dozen days between now and June, electing an upper and lower house, approving a constitution and electing a president. The authorities in Egypt have done little to educate voters about the elections, beyond running simple cartoons on state television.
"We are all lawyers, so we are supposed to know what to do, and we are still trying to figure it out!" said Mohamed Gamal, 33, walking with two friends in Sayed Zeinab.
"I don't understand anything - I don't know what to do at all," complained a woman passing by.
But when she declined to give her name, Mr. Gamal smiled at her. "Don't be so scared - there is no Mubarak," he said.