Health workers manned polling stations across Liberia on Saturday as voters cast their ballots in a twice-delayed Senate election that has been criticized for its potential to spread the deadly Ebola disease.

A total of 1.9 million voters are registered to participate in 15 Senate races throughout the country contested by 139 candidates.

Originally scheduled for October, the vote was pushed back to Dec. 16 as Liberia struggled to contain the Ebola epidemic, which has killed nearly 3,300 people in the country. Officials then pushed it back four more days to Saturday.

The disease appears to have slowed in recent weeks in Liberia, though critics questioned whether the vote could be conducted safely and credibly.

The outbreak has now killed more than 7,000 people in total, the World Health Organization reported late Friday, though many of the latest deaths have occurred in Sierra Leone. The three countries hit hardest by Ebola—Liberia, Sierra Leone and Guinea—have now recorded 7,373 deaths, up from 6,900 on Wednesday, the WHO said.

Liberian officials distributed 4,700 thermometers and 10,000 bottles of sanitizer to polling stations in preparation for Saturday's election. Earlier in the week, Assistant Health Minister Tolbert Nyenswah warned that anyone running a temperature higher than 98.6 degrees Fahrenheit could be removed from the line and sent for screening. A sudden fever is one of the signs of Ebola infection.

"Let's fight to the last until the last Ebola case is gone out of this country," Nyenswah said.

On a visit to Liberia Friday, United Nations Secretary-General Ban Ki-moon urged voters to follow health guidelines "to protect yourself and your loved ones" from the disease, which is spread through contact with the bodily fluids of sick people.

"This election will give Liberia and its people an opportunity to show the world how far it has come," Ban said.

The most high-profile race, in Monrovia's Montserrado County, pits opposition leader George Weah against Robert Sirleaf, son of President Ellen Johnson Sirleaf.

Weah, a former soccer star who won the first round of voting for president in 2005 before losing in a runoff, said Saturday he would "flog" Robert Sirleaf, who he described as "unpopular."

Sirleaf could not be reached Saturday, but he has previously called on Weah "to debate the issues and not personalities."

No debate between the candidates was ever held.