Protesters have called for the replacement of Prime Minister Yingluck Shinawatra with an unelected council that would push for electoral change, CNN reported.
The demonstrations and ensuing conflicts have left 10 people dead and hundreds more injured.
Yingluck, the sister of exiled former Prime Minister Thaksin Shinawatra, called for the elections in December to ease tensions. But main opposition party has already rejected the ballotting, which Yingluck's Pheu Thai party is expected to win.
Protesters have blocked candidate registration and early registration sites. Their efforts have led to clashes with authorities, who have ramped up security ahead of the vote.
Protest leaders said they are hoping to shut down the city Sunday to prevent the election.
Yingluck has refused to postpone the election.
"The election is one of the best and peaceful mechanisms to end conflict between people of different political views, and a way to reflect majority's needs and minority's voices," Yingluck said in a statement Thursday.