By Marwa Awad
CAIRO (Reuters) - Egypt holds a referendum on Saturday on constitutional changes in the first such vote since protests toppled longtime president Hosni Mubarak.
The referendum, designed to usher in free legislative and presidential elections, has divided the country's reform movement between those in favor of amending the constitution and those who want it completely rewritten.
The Muslim Brotherhood, Egypt's biggest organized opposition group, and other Islamists support the amendments.
Other opposition parties and prominent reformists, including prospective presidential candidates Mohamed ElBaradei and Amr Moussa, oppose them.
A high turnout is expected and the referendum could go a long way to restore faith in elections, which were marred by violence and vote-rigging under Mubarak's rule.
"The referendum is an important step from a democratic viewpoint because Egyptians feel the result is in their hands and no one else's," political analyst Diaa Rashwan said.
Some 45 million of Egypt's 80 million people are eligible to vote.
"Things will be different from now onwards, no more sham elections, no more thugs chasing voters away," prospective voter Youssef Ali, 29, said.
"I have never voted in my life because with Mubarak free elections were impossible. But today my vote will count."
The military council, which took power from Mubarak on February 11 after he stepped down in the face of mass protests, hopes the changes will pass, enabling it to hold parliamentary and presidential polls and cede power to an elected government within months.
It called for a high turnout and said participation in a free electoral process was more important than the outcome. The army will deploy 37,000 soldiers to help police forces secure the streets.
Rejecting the amendments will force the council to extend an interim period, which it wants to keep as short as possible, and to form a new judicial committee to re-write the constitution.
That scenario could push back a parliamentary election to December, a security source said, four months later than the September vote the military is planning at the moment. The presidential election is expected after the parliamentary one.
The European Parliament said 14 of its members will monitor the referendum and meet with Muslim Brotherhood members and activists in a short trip to Egypt, the state-run MENA news agency reported.
Polls open from 8 a.m. until 7 p.m. (0600-1700 GMT).
(Additional reporting by Sherine El Madany; Writing by Marwa Awad; Editing by Michael Roddy)