Leading Salafis hinted in recent days that they did not expect quick fulfillment of their goals for a state governed by Islamic law. Instead , they wanted a president who could deal with Egypt’s pressing needs while allowing them freedom to preach and advocate.

“We don’t want the sheik of Islam,” Sheikh Hassan Omar, a Salafi leader and lawmaker in the upper house of Parliament from the Delta province of Behaira, said this week as Mr. Aboul Fotouh was campaigning nearby.

But the Salafi endorsement also appeared to provide an unexpected validation for Mr. Aboul Fotouh’s argument that mixing preaching and politics would be “disastrous” for both Islam and Egypt, as he put it in an interview last week with El Rahma, a major Salafi satellite channel.

Mr. Aboul Fotouh, a physician who led the Brotherhood-dominated medical association, was a founder of a 1970s student movement that revitalized Islamist politics here. He was expelled from the Brotherhood last year for defying the decision of its leaders to bar members from running for president or engaging in politics outside its own political party.

Although the Salafis are more conservative on many cultural issues, they also typically disapprove of the Muslim Brotherhood’s emphasis on internal obedience and orthodoxy.

In recent interviews with Salafi satellite networks, Mr. Aboul Fotouh has explained that his candidacy and his expulsion from the Brotherhood are part of a larger dispute over whether in a democratic Egypt the Brotherhood should control its own political party, or instead go back to its roots in preaching and charity while its members apply their own values to political life.

In some interviews, he has alluded to threats to the credibility of religious leaders in the unseemly day-to-day of political life, ranging from the appearance of compromises in the interest of power to more vivid embarrassments like the recent case of a Salafi lawmaker who was caught fabricating a beating by unknown assailants to cover up a nose job.