A resolution to this effect was adopted at the party's high-level committee meeting held in Chennai.
The decision had been taken considering that elections to the Tamil Nadu assembly, due next year, could be advanced to December this year, it said.
Further, the party also alleged that the ruling party could engage in money distribution.
The Radhakrishnan Nagar by-poll, necessitated by the resignation of the AIADMK's P Vetrivel on May 17, is expected to be a cakewalk for party chief Jayalalithaa, who has already returned as chief minister for the fifth time following her acquittal in a wealth case by the Karnataka high court last month.
She has to be elected to the assembly within six months.
Jayalalithaa was disqualified as chief minister and MLA in September last following her conviction in the Rs 66.66 crore disproportionate assets case by a lower court.