The results of the first round of Egypt's presidential election are at once hugely positive, and hugely negative.

They are hugely positive because they show that by far the biggest of the Arab Spring countries has more or less successfully embraced the democratic process. Some 16 months after the overthrow of Hosni Mubarak, Egypt has elected a lower house of parliament and looks set to elect a President.

Despite periodic doom-mongering and a few localised clashes, the country has not descended into violence, nor have the elections been discredited by widespread violations. Not everything has been perfect, but the process has been cleaner and better organised than many anticipated. It is to be hoped that this impression is not contradicted by anything that might come to pass before the run-off next month.

It is here, in the choice produced by the first round of voting, that the hugely negative assessment comes in. When the crowds of mainly young protesters took to the streets in January 2011, there was a spirit of enormous optimism and excitement in a new start. Tahrir Square became the emblem for the change promising to sweep across the Arab world. That the revolution triggered a mercifully brief civil war in Libya and now appears to have stalled, with much bloodshed, in Syria does not diminish what has been achieved, mostly peacefully, in Egypt.

What is regrettable is the way this young, generally moderate and secular swathe of society has largely vanished from view. As in so many revolutions, the forces that created it have split. The effect is to leave Egyptian voters with the very same polarised alternatives that helped fuel the uprising in the first place: on the one hand is the Muslim Brotherhood, formerly banned from politics; and on the other, the forces of conservative and secular patriotism represented by the Mubarak clan.

The two names on the ballot paper on 17 June will be those of Mohamed Morsi of the Freedom and Justice Party – the political wing of the Muslim Brotherhood – and Ahmed Shafik, the ousted President's last Prime Minister. The forces that made the revolution were too fragmented to produce a second-round contender.

All is not lost. Neither candidate can win only by consolidating his own constituency. They must both seek to appeal more widely. Mr Morsi has his eyes set on the more conservative Muslims, whose favoured candidates did unexpectedly well in parliamentary elections. Mr Shafik, to his credit, is pitching for the votes, among others, of the young revolutionaries. But he faces several obstacles, among them his close association with the Mubaraks and the military, which tends to obscure the reputation for competence he built up as air force chief and then Civil Aviation Minister in the early 2000s.

An even greater handicap might prove to be the disappointment and disaffection now felt by younger voters. Although queues built up at many polling stations, the first-round turnout was lower than had been hoped, and could fall below 50 per cent in the second. Questions might then be asked about the new President's credibility, and the extent to which he will be able to fulfil his mandate.

This is not to underestimate what has happened in Egypt. An orderly and genuinely contested election for President is a considerable achievement in itself. But if its democracy is to grow sturdy roots, Egypt needs a leader who can command respect across its political and religious divides.