The rally in Mansura, a university town half way between Cairo and the Mediterranean Sea, drew students dressed in T-shirts bearing his image, as well as activists ranging from doctors to taxi drivers.
"Everyone in Mansura is with ElBaradei. We want change, we support him because we want anyone other than the regime. We have no alternative than ElBaradei," said Hisham, a 26-year-old engineer.
ElBaradei, 67, has said he is willing to stand against President Hosni Mubarak in 2011 on condition that the election is free and fair and that the constitution is revised to ease candidacy restrictions.
The 2005 Nobel Peace Prize winner visited a medical centre at Mansura University, meeting kidney transplant pioneer Mohammed Ghoneim, before heading to Al-Nur mosque for Friday weekly prayers.
His plans to go to Mansura's Sheikh Hassanein mosque were rejected by security services, an official from his newly formed National Association for Change told AFP.
Watched by police but without a personal bodyguard, a smiling ElBaradei was dressed in a white shirt as he greeted supporters who had to negotiate a throng of cameramen to get close enough to shake his hand.
Among his admirers were youthful members of opposition movements, including the officially banned but tolerated Muslim Brotherhood. Some asked those present to sign a petition to support ElBaradei.
"This time, I feel that it is serious. He is responsible and I am hopeful he will succeed," Aya, a 21-year-old medical student, said as she waded into the crowd.
"People in Egypt do not speak of their low wages and high cost of living, but nothing will improve without democracy and an alternative in power," she said.
Ibrahim Abul Ata, a 41-year-old migrant worker based in the United Arab Emirates, said he had put off his return to the Gulf state so he could see the former head of the Vienna-based International Atomic Energy Agency.
"I had to leave on Wednesday, but when I learned ElBaradei was coming, I delayed my departure," he told AFP.
"I wanted to see this man who wants to do something good for our children. We need the outside world to know that the Egyptian people are with him."
Hamdi Hadidi, a renowned orthopaedic surgeon, said he believes ElBaradei returned to Egypt last month "to open the way (for reforms) even if he does not end up as president."
But some ElBaradei supporters have already run into trouble with the security services for openly backing him.
Last month, a non-governmental group reported that a doctor in the central town of Fayyum was abused and beaten for supporting ElBaradei.
In Mansura, Ashraf Wagdi, a psychiatrist who actively campaigns for the former diplomat, told AFP that police arrested and detained him for 24 hours last week on the "pretext" he owns a bookstore whose papers were not in order.
But Wagdi said he saw signs of hope on Friday when the prosecutor handling his case himself came to sign the petition in support of ElBaradei.
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