Thai election officials have warned that it could take several weeks to re-stage voting in areas where Sunday’s election was disrupted by protesters.
The anti-government protesters halted voting in parts of Bangkok and the south by blockading polling stations.
Their actions rendered millions of people unable to vote.
The ruling party of Yingluck Shinawatra is expected to win the election but legal challenges and a lack of MPs may create a political limbo.
The disruption means not all seats in parliament will be filled, requiring by-elections in many places.
The government wants elections that were disrupted to be re-run as soon as possible – a new parliament cannot sit until 95% of seats have been filled, reports the BBC’s Jonathan Head.
But the official election commission has warned it may take weeks to hold by-elections in so many constituencies.
Prime Minister Yingluck Shinawatra called the snap election after a sustained campaign by the protesters. She said on Sunday that going to the polls had been the right thing to do.
“At least I think at this election it is very important that people come out to vote for their right to democracy,” she said.
Protest leader Suthep Thaugsuban, however, told supporters late on Sunday he was “confident this election won’t lead to the formation of a new government”.
Thailand’s Election Commission said six million voters were affected by disruption on Sunday, but 89% of polling stations operated normally.
On Monday protesters again took to the streets, marching through parts of Bangkok.
“We are not giving up the fight. We still keep fighting,” Suthep said. “Our mission is to keep shutting down government offices, so don’t ask us to give those back.”
The protesters are to reduce the number of major road junctions they have blockaded in Bangkok from seven to five. They cited fear of attack as the reason, though some observers pointed to dwindling numbers. The protesters want the government to be replaced with an unelected “people’s council” to reform the political system. They allege that Ms Yingluck’s government is controlled by her brother, ousted leader Thaksin Shinawatra. They accuse Thaksin-allied parties of buying rural votes with ill-judged schemes that hurt the economy. The main opposition Democrat Party, which is allied to the protesters, has been unable to win a majority in parliament for more than two decades.
The opposition says it will challenge the poll as it “did not reflect the intention of the constitution or the people”.
Ms Yingluck’s party is already facing a host of challenges in the courts that could force it from power, as has happened with pro-Thaksin parties in the past.
Reuters, adds: Thai anti-government protesters who have been camped out in north Bangkok packed their tents and marched downtown on Monday as they consolidated efforts to topple Prime Minister Yingluck Shinawatra, a day after a disrupted general election.
Some joined protest leader Suthep Thaugsuban on foot and others followed in cars and six-wheel trucks as Thailand’s long-running political conflict showed no sign of ending.
Others surrounded a government office in north Bangkok where Yingluck and two senior ministers had been holding a meeting and cut through a barbed-wire fence. They did not enter the building and it was unclear if Yingluck was still inside.
The protesters closed camps at two of the seven big intersections that they have blockaded since mid-January, at Victory Monument and Lat Phrao, and were heading for the fringes of the central oasis of Lumpini Park.
A third camp run by an allied group at a big government administrative complex may also be closed.
Suthep said on Sunday this was being done out of safety concerns, but it could also be because their numbers are dwindling. Reuters put the number of marchers at about 3,000, with hundreds surrounding the government office.
