The Election Commission will announce the dates of the assembly elections in Maharashtra and Haryana at noon. The dates for Jharkhand polls will not be announced together with the two states.
As per sources, polling could take place in Maharashtra and Haryana before Diwali on October 27.
The model code of conduct will be in place in these states as soon as the dates are announced.
BJP and its ally Shiv Sena have already kick-started their campaign. A Maha Jan Aadesh Yatra was carried out last month by BJP's Chief Minister Devendra Fadnavis to reach out to voters across Maharashtra. At the end of the roadshow, Prime Minister Narendra Modi addressed a rally on Thursday.
However, the opposition Congress and Nationalist Congress Party appear to be facing an exodus of politicians switching to the BJP or Sena.
The BJP won Maharashtra in the 288-member assembly with 122 seats, defeating the government of Congress.
Also in the 90-member Haryana assembly, the governing party won a majority for the first time, leaving Congress out of power after two straight terms.