When you think of Egypt's Tahrir Square revolutionaries, Amr Moussa just doesn't fit.

Far from hurling rocks and insults at the former regime of Hosni Mubarak, he was once part of it. A high-profile Cairo insider, he served as Egypt's foreign minister for 10 years, then as the head of the pro-establishment Arab League for another decade.

And yet, as the dust settles on this revolution, the 75-year-old Moussa could well end up in power, the replacement for the disgraced Mubarak.

Heading into presidential elections that begin on Wednesday, he is seen by many as the front-runner.

It's not exactly what those who risked their lives in Tahrir Square last year might have imagined when they were staring down the police and the military, ducking bullets and dodging stampeding camels.

But then, little about this election has been predictable. Time and again, the ruling generals in the transitional government left doubts about whether it would even happen.

The generals certainly haven't seemed eager to pass power to the people. But that hesitancy has been only one of the many twists and turns in this long drama.

One big one was that the secular, liberal and left-leaning groups that inhabited the iconic square last year, forcing Mubarak's ouster, couldn't come up with a single compelling candidate for the presidency.

Hosni Mubarak's former foreign minister, Amr Moussa, seen here greeting supporters in Cairo earlier this week, is a leading candidate for the presidency. (Mohamed Abd El Ghany / Reuters)

The Muslim Brotherhood, Egypt's largest and once banned political movement did — a wealthy and charismatic nominee, Khairat el-Shater, only to see him disqualified because he had been jailed under Mubarak.

In fact, 10 of the 23 would-be candidates were recently ruled ineligible by Egypt's presidential election panel, leading to more protests, more injuries on the streets and more jailing in recent weeks.

Three of those disqualified had been considered front-runners. And so many assumptions of who might win were thrown out with them.

Ultra-rivals

The Brotherhood's back-up choice, Mohammed Morsi, will still likely do well because his Islamist party is respected and its campaign well-financed.

But he's been overshadowed by another, surprisingly strong candidate, Abdel Moneim Aboul Fotouh, a Cairo physician, former Brotherhood leader (until he was kicked out for challenging Brotherhood policies) and long-time anti-Mubarak dissident.

Polling in Egypt is far from reliable, but several surveys have picked up a surge by Aboul Fotouh, now considered the strongest challenger to Moussa. The two men couldn't be more different.

While Moussa served Mubarak, Aboul Fotouh was persecuted by him because of his political and religious views.

In recent weeks, he has emerged as the leading voice for many of those who have long been outsiders in Egypt: liberal Islamists, some prominent feminists and Marxists, and — most surprisingly — the country's ultra-conservative Islamist movement, the Salafis.

That's strange because Aboul Fotouh himself is known for his open-minded and inclusive interpretation of Islam, while the Salafis preach a strict, some say medieval, enforcement of Islamic law.

But Salafi leaders see the endorsement as a way to check the ambitions of their rivals, the Brotherhood, which dominated parliamentary elections earlier this year and has been trying to flex its political muscle ever since.

A presidential win could give it a real lock on power, limited only by whatever control the generals decide to keep.

Why Moussa?

Aside from their core religious beliefs, the two movements, the Brotherhood and the Salafis, are politically quite different.

The Brotherhood is led by ambitious businessmen and professionals, with a right-leaning economic agenda. The Salafis, on the other hand, represent the grassroots of Egyptian society, and rejected political participation altogether until these elections.

Will the generals loosen their grip on Egypt's presidency? A Cairo graffiti artist doesn't think so and has made his views known on a wall near Tahrir Square. (Amr Dalsh / Reuters)

They came in second to the Brotherhood in the parliamentary elections earlier this year, taking 28 per cent of the vote to the Brotherhood's 38 per cent of the vote (and 47 per cent of the seats).

So with all that popular support for Islamist parties, how did a secular, former Mubarak official like Moussa end up as a front-runner?

Well, for one, he's been playing on two big fears that Egyptians have of their future.

First, while the vast majority of Egyptians consider themselves devout Muslims, it's not so clear how many actually want to live in a state defined by religion.

Moussa has raised the spectre of an overbearing and risky "Islamist experiment" if his rivals win.

Just as important, he's been promising a return to stability and prosperity.

Sure, most Egyptians cheered the success of the initial uprising and the ouster of Mubarak, but they've been increasingly annoyed by continuing clashes and disruptions.

Many blame the protestors for the fewer tourists this year as well as lost jobs and an economy in tatters. In Cairo, even the traffic jams around Tahrir Square seem to fray nerves.

Can the promise of a new democracy actually solve those problems? Can any of the candidates? Probably not.

No matter who wins, the first presidential term in the new Egypt is likely to look a lot like the last few months of the old one. So deep are the problems in the country, economic frustrations will only grow, and could even spill over into fresh protests.

What's more, even if the generals keep their promise and formally hand over power to an elected president by July 1, their own influence — maybe even control — isn't going to diminish much.

Every one of the leading candidates has promised to let the military keep its budget and its say in the choice of a new defence minister, as well as keeping its grip on a dizzying array of profitable businesses that the army owns: from hotels to consumer electronics to bottled water.

Just last week, the head of the interim government, Field Marshall Mohamed Hussein Tantawi said the military has a "sacred duty" to protect Egypt from domestic disturbances no matter who is president, or what anyone says.

"God willing, we'll the cut the tongues of those who make false allegations against our troops and men," he said in a speech to new soldiers.

Whoever wins will certainly have his work cut out for him.