More than 15 months after autocratic leader Hosni Mubarak's ouster, Egyptians streamed to polling stations Wednesday to freely choose a president for the first time in generations. Waiting hours in line, some debated to the last minute over their vote in a historic election pitting old regime figures against ascending Islamists.

A sense of amazement at having a choice in the Arab world's first truly competitive presidential election pervaded the crowds in line. At the same time, voters were fervent with expectations over where a new leader will take a country that has been in turmoil ever since its ruler for nearly 30 years was toppled by mass protests.

Some backed Mubarak-era veterans, believing they can bring stability after months of rising crime, a crumbling economy and bloody riots. Others were horrified by the thought, believing the "feloul" -- or "remnants" of the regime -- will keep Egypt locked in dictatorship and thwart democracy.

Islamists, particularly the Muslim Brotherhood, saw their chance to lead a country where they were repressed for decades and to implement their version of Islamic law. Their critics recoiled, fearing theocracy.

"You can't tell me, 'Vote for this or else you're a sinner!"' Wael Ramadan argued with an Islamist-backer in line at a polling station in the impoverished Cairo neighborhood of Basateen. "We never said that," protested the man. "Yes, you did," Ramadan shot back.

"The revolution changed a lot, for good and bad," Ramadan, a 40-year-old employee at a mobile phone company, said afterward. "The good thing is all this freedom. We are here and putting up with the trouble of waiting in line for electing a president. My vote matters ... Now we want a president who has a vision."

A field of 13 candidates is running in Wednesday and Thursday's voting. The two-day first run is not expected to produce an outright winner, so a runoff between the two top vote-getters will be held June 16-17. The winner will be announced June 21. Around 50 million people are eligible to vote. Turnout so far appeared moderate, and Wednesday's vote was extended another hour.

An Islamist victory will likely mean a greater emphasis on religion in government. The Muslim Brotherhood, which already dominates parliament, says it won't mimic Saudi Arabia and force women to wear veils or implement harsh punishments like amputations. But it says it does want to implement a more moderate version of Islamic law, which liberals fear will mean limitations on many rights.

Many of the candidates have called for amendments in Egypt's 1979 peace treaty with Israel, which remains deeply unpopular. None is likely to dump it, but a victory by any of the Islamist or leftist candidates in the race could mean strained ties with Israel and a stronger stance in support of the Palestinians in the peace process. The candidates from the Mubarak's regime -- and, ironically, the Brotherhood, which has already held multiple talks with U.S. officials -- are most likely to maintain the alliance with the United States.

The real election battle is between four front-runners.

The main Islamist contenders are Mohammed Morsi of the powerful Brotherhood and Abdel-Moneim Abolfotoh, a moderate Islamist whose inclusive platform has won him the support of some liberals, leftists and minority Christians.

The two secular front-runners are both veterans of Mubarak's regime -- former prime minister Ahmed Shafiq and former foreign minister Amr Moussa.

A major worry is whether either side will accept victory by the other. Many Islamists have warned of new protests if Shafiq wins, saying his victory could only come from fraud. Some believe the ruling military is determined to see Shafiq, a former air force commander, win.

"Over my dead body will Shafiq or Moussa win. Why not just bring back Mubarak?" said Saleh Zeinhom, a merchant backing Abolfotoh. "I'm certain we'll have a bloodbath after the elections cause the military council won't hand power to anyone but Shafiq."

So far, there were only a few reports of violations of election rules Wednesday, mainly candidates' backers campaigning near polling stations -- though observers said it was far less than during parliament voting. In some villages around Cairo on Wednesday, Brotherhood backers were seen whispering Morsi's name to voters in line.

Along with several Egyptian groups, three international monitoring organizations, including the U.S.'s Carter Center, were observing the vote, along with multiple Egyptian groups. Former President Jimmy Carter, the center's head, visited a polling station in the ancient Cairo district of Sayeda Aisha.

The election's winner will face a monumental task. The economy has been sliding. Crime has increased. Labor strikes have proliferated.

And the political turmoil is far from over. The military, which took power after Mubarak's fall on Feb. 11, 2011, has promised to hand authority to the election winner by the end of June. But many fear it will try to maintain considerable political say. The fundamentals of Mubarak's police state remain in place, including the powerful security forces.

"The pressure will continue. We won't sleep. People have finally woken up. Whoever the next president is, we won't leave him alone," said Ahmed Maher of the group April 6, a key architect of the 18-day uprising against Mubarak.

The country must still write a new constitution to define the president's powers. That was supposed to be done already, but was delayed after Islamists tried to dominate the constitution-writing panel, prompting a backlash that scuttled the process for the moment.

The Muslim Brotherhood is hoping for a Morsi victory to cap their political rise, after parliament elections last year gave them nearly half the legislature's seats.

In the Mediterranean city of Alexandria, microbuses run by the Brotherhood ferried women supporters to the polls in the poor neighborhood of Abu Suleiman, one of the group's strongholds. The women, in conservative headscarves or covered head to toe in black robes and veils that hid their faces, filed into the station.

"I want to give the Brotherhood a chance to rule," said Aida Ibrahim, a veteran Brotherhood member helping voters find their station. "If it doesn't work, they will be held accountable," she said.

Some Brotherhood supporters cited the group's years of providing charity to the poor -- including reduced-price meat, and free medical care. "Whoever fills the tummy gets the vote," said Naima Badawi, a housewife sitting on her doorstep watching voters in Abu Sir, one of the many farming villages near the Pyramids being sucked into Cairo's urban sprawl.

But some who backed the Brotherhood in the parliament election late last year have since been turned off.

In many places, the argument went right up to the doorsteps of the schools where voting was held. In the village of Ikhsas, outside Cairo, a group of neighbors got into a friendly but frank debate outside the polling station.

"I voted Brotherhood for parliament but I find they are inflexible in their opinions and want to take everything. I can't now find them in the country's top job," Bassem Saber, a 31-year-old accountant dressed in the traditional local robes, told the circle of men. He now backs Abolfotoh, who was ejected from the Brotherhood last year.

Khaled el-Zeini, a Brotherhood backer, said people were being unfair because the military blocked the group's majority in parliament from forming a government.

"We loved them and wanted them but we realized they are all about monopolizing power," Fares Kamel, a local trader, interjected, referring to the Brothers.

The secular young democracy activists behind the anti-Mubarak uprising have been at a loss, with no solid candidate reflecting their views.

In Cairo, 27-year-old Ali Ragab supports a leftist, Hamdeen Sabahi -- because the poor "should get a voice" -- but he admitted Sabahi didn't stand much of a chance.

He said his father and his father's friends were voting for Shafiq, thinking he will restore security. "I'm afraid Shafiq would mean another Mubarak for 30 more years."

For most of his rule, Mubarak -- like his predecessors for the past 60 years -- ran unopposed in yes-or-no referendums. Fraud guaranteed ruling party victories in parliamentary elections. Even when Mubarak let challengers oppose him in 2005 elections, he trounced his liberal rival and then jailed him.

Two weeks from now, a court is due to issue its verdict on Mubarak, 84, on trial on charges of complicity in the killing of some 900 protesters during the uprising. He also faces corruption charges, along with his two sons, one-time heir apparent Gamal and wealthy businessman Alaa.

The feeling of choosing at long last was overwhelming for some voters.

Medhat Ibrahim, 58, who suffers from cancer, waited in line at a Cairo poll.

"I might die in a matter of months. So I came for my children, so they can live," he said, breaking into tears. "We want to live better, like human beings."