About 30 people camped out in front of the Sai Mai district office to prevent possible poll disruption by protesters with the People's Democratic Reform Committee, the Bangkok Post reported.
The PDRC does not want the elections to take place, and would rather see Thailand's current government be replaced by non-elected officials.
More pro-election Thais headed to Thailand's far south to stop possible attempts to derail voting there on Sunday.
Abdullah Ma-sae, deputy chief of the Pattani provincial administration organization in southern Thailand, read a statement Saturday saying PDRC is violating people's rights under the democratic system if it attempts to block voters from entering polls. Abdullah said he and a group of local residents and officials would not sit by and let the PDRC disrupt polling.
Thailand's Election Commission was still in need of 44,000 officials to staff polling stations as of Friday, the Bangkok Post said. A total of 93,305 polling stations will be operating nationwide from 8 a.m. to 3 p.m.
Thailand's southern provinces are most in need of election officials -- no staff has been registered to work at polling stations in Surat Thani or Songkhla provinces. Polling stations in Bangkok still need about 4,000 workers.
Thai Prime Minister Yingluck Shinawatra's party will likely win the elections, but could face legal challenges after the vote, Voice of America reported.
"Judging from the current situation, it's going to be very difficult to carry on the election. There's no hope for success -- and they cannot prolong. The peaceful move against the government is doing quite well actually, and the government, now to see how long they are going to stand for it," said Dej-Udom Krairit, president of the Lawyers Council of Thailand.