According to an election official, four candidates each of Congress and BJP were among the 23 candidates who filed nomination papers for the four constituencies of Surajgarh, Weir, Nasirabad, and Kota (South), the official said.
Scrutiny of papers will take place tomorrow and the last date of withdrawal would be August 30.
BJP, which was to announce its candidate for Surajgarh assembly seat, has fielded former Health and Medical Minister Digamber Singh as its nominee from the constituency.
Bypolls were necessitated in the four assembly seats of Rajasthan as they fell vacant after the sitting MLAs were elected to Lok Sabha.