A low voter turnout in the Egyptian presidential election is threatening to derail former army chief Abdel Fattah al-Sisi's mandate to become the country's next president.

According to Reuters, a member of the election committee said more than 21 million people voted, which is only 39 percent of the 54 million electorate. That number is well below the 40 million votes, or 80 percent of the electorate, that Sisi called for last week to ensure his ascension to the presidency.

Yet, a Western official following the polling says turnout was between 10 and 15 million votes, which is between 19 and 28 percent of the electorate, far less than what was initially projected.

The low voter turnout suggests that Sisi has not rallied the support he intended to harness after ousting Mohamed Mursi, Egypt's first democratically-elected president following the overthrow of Hosni Mubarak.

The lower turnout is expected to be linked to political apathy and the country's opposition to another military leader becoming president. Many in the politically divisive country are also opposed to the suppression of dissent among liberal youth.

The two-day vote was supposed to end Tuesday, but was extended until 9 p.m. Wednesday to allow more voters to get out to the polls.

Eric Bjornlund, the president of Democracy International, said that the extension of polling has raised doubts about Egypt's electoral process.

"Last-minute decisions about important election procedures, such as a decision to extend polling by an additional day, should be made only in extraordinary circumstances," Bjornlund said.

Although Sisi posted photos of long voting lines on his Facebook page, no long lines could be seen in Cairo.

"You want to speak with voters? Do you see any voters? I don't know why they're not coming, maybe they reject politics," said an army officer outside a Cairo polling station.

Despite a campaign to bring out voters, many Egyptians lack enthusiasm about the election.

The Muslim Brotherhood, which was outlawed by the military as a terrorist group, is opposed to the former army chief taking power.

"Holding these elections is null and void under the military coup ... It cannot be legitimized by elections or in any other way," said Muslim Brotherhood member Mohamed Abdel Hafeez.

Secular activists who backed the ouster of Mursi are also discontent with Sisi after activists were arrested amidst a security crackdown.

"The low turnout is a slap in the face for Sisi. I hope he now sees that he only has the votes of old women and men but not us, the youth, who are the majority in this country," said Mohamed Ahmed, a 26-year-old from Cairo.

Many Egyptians also do not believe that Sisi has a clear plan for how to prevent Egypt's poverty and energy crisis.