By Tom Perry
CAIRO (Reuters) - The Muslim Brotherhood's chances of winning the Egyptian presidency have been damaged by the decision of a hardline Islamist movement to back its main rival in a race that heats up on Monday with the start of official campaigning.
The historic democratic election to decide who replaces fallen autocrat Hosni Mubarak has become a political struggle between Islamists who were oppressed by the deposed president, politicians who at some point were part of his government and liberals and leftists seen with little chance of winning.
Some 53 million Egyptians will be eligible to vote on May 23-24 in a first round that is expected to be followed by a June run-off between the top two candidates. The ruling military council is due to hand over power on July 1.
The Nour Party of the Salafi movement, which espouses a puritanical version of Islam, on Saturday endorsed Abdel Moneim Abol Fotouh, a former Brotherhood member, for the presidency.
That should bring to Abol Fotouh a lot of the votes that propelled the Salafis into second place behind the Brotherhood in Egypt's parliamentary elections.
It was the latest boost to an Abol Fotouh campaign buoyed by the disqualification of other top Islamist contenders, including the Brotherhood's first-choice candidate, and the broader support he has built across the political spectrum.
"This is a big blow to the Brotherhood. It could even be considered the biggest blow yet," said Shadi Hamid, an expert on Islamist groups based at the Doha Brookings Center. "The Brotherhood has to think seriously about the perception of being defeated, and defeated by Abol Fotouh."
Abol Fotouh was ejected from the Brotherhood last year when he decided to defy its wishes by running for the presidency. He is described by Brotherhood experts as a reformist who was at odds with more conservative figures who now lead the movement.
Mohamed Mursi, the Brotherhood's candidate, will go on the campaign trail on Sunday in southern Egypt. "This creates an incentive for our members to make more effort," said Mahmoud Ghozlan, spokesman for the Brotherhood, commenting on the Nour Party's decision to back Abol Fotouh.
The Nour Party and al-Daawa al-Salafi, the religious movement to which it belongs, decided at a meeting on Saturday to back Abol Fotouh after its board heard presentations from the top Islamist candidates.
"We see him as the most appropriate person for this period," said Mohamed Nour, a spokesman for the Nour Party. "He does not belong to any party and he adheres to principles and the project of Islamic civilization to a great extent," he said.
"We will only pick someone who is the best for leading Egypt, even if we disagree with him in some ideological matters," he added, without elaborating.
Abol Fotouh, 60, has presented himself as a moderate Islamist, talking about a vision of sharia (Islamic law) that promotes the interest of society at large, though critics say he has yet to clarify exactly what that means.
His support base includes some of the liberals who had supported Mohamed ElBaradei, the Egyptian former head of the U.N. nuclear watchdog who withdrew from the race in January.
The Brotherhood, founded in 1928, had been dismissive of the Salafi parties that were set up last year. But after deciding at the end of March to throw its hat into the presidential ring, the Brotherhood sought to rally the Salafis to its side.
But as it has courted the conservative right, the Brotherhood has faced ever sharper criticism from liberal reformists and others who say it has rowed back on promises that it would not seek to dominate the post-Mubarak era.
One area of dispute has been who should draft a new constitution that could well curb presidential powers, casting doubt on how much authority the incoming head of state will have. Another unresolved question is how much power the long influential military might continue to wield behind the scenes.
Seeking to break the constitutional impasse, the military council met political parties on Saturday and reached what state media described as an agreement on how the 100-person body that is to draft the constitution should be formed.
Participants described the deal as "a general framework", indicating there could be more discussion ahead.
(Additional reporting by Marwa Awad and Dina Zayed; Editing by Mark Heinrich)