DMK president M K Stalin is scheduled to campaign for the party's candidate in Dharapuram Assembly constituency on Friday, the party said.
The DMK has fielded S Suganya in the AIADMK stronghold, where former MLA P Sathyabama resigned from the Assembly and joined the ruling TVK days after the 2026 Assembly election results were announced, leading to the by-election scheduled for October 6.
Chief Minister C Joseph Vijay-led TVK has nominated Sathyabama to contest from the constituency, while the AIADMK has fielded K Bhanumathi to take on her.
The AIADMK is keen to retain the seat in the high-stakes by-election, in which the DMK is contesting on its own after its key allies, the Congress, VCK and IUML, joined the TVK alliance.
Stalin will hold a roadshow from the Amaravathi statue to Periya Kadai Veethi and later address an election rally on Udumalpet Road in the evening.
Following the Dharapuram campaign, the former CM will campaign in Madurantakam Assembly constituency on October 3 in support of party candidate I Paranthamen.