Chhattisgarh's ruling Bharatiya Janata Party (BJP) and the main opposition Congress will battle it out for the lone assembly seat that goes to polls on Saturday.
The BJP, which is in power since December 2003, is pulling no stops to retain the seat which was vacated by its legislator Saroj Pandey.
Pandey was elected to the Lok Sabha in May.
Fifteen candidates are in the fray but the main fight is between Jageshwar Sahu of the BJP and Bhajan Singh Nirankari of the Congress. The Bahujan Samaj Party (BSP), the third force in the state, has opted out of the contest.
The seat in Durg district has a little over 211,000 voters with 40,000 of them migrants from Uttar Pradesh and Bihar.
"We don't want to give Congress any chance of making a comeback in the state. The voters' response during campaigning has convinced me that party will retain the seat with comfortable margin again," Pandey said.
Pandey had won the seat in November 2008 with a margin of 22,000 votes.
The Congress leaders, who displayed a rare unity during the campaign, claim the BJP is set to suffer defeat.
"Voters are determined to teach a lesson to BJP as they ensured its victory in November polls with a comfortable margin with a hope that party MLA (member of legislative assembly) will serve the voters for five years and will ensure development. But the sitting MLA resigned from the seat within six months," Dhanendra Sahu, state unit Congress president, said.
"What was the need of by-poll if BJP MLA had not been resigned? Voters were forced to chose another MLA and that was the issue Congress raised prominently during campaigning," he said.
Former chief minister Ajit Jogi and party's national treasurer Motilal Vohra campaigned extensively for the Congress candidate.