Salem Election Officer and Collector K Maharabhushanam had announced that no one should carry more than Rs 50,000 without documents.
Police said Rs 5,15,500 was seized from the jeep. The driver and a construction supervisor who were travelling in the vehicle said the money was for the labourers' weekly salary but did not have any documents to account for it, police said.
The money and jeep were seized and handed over to the District Social Welfare Officer, Sabapathy.
DMK Rajya Sabha MP T M Selvaganapathi and party district secretary S R Sivalingam wanted to know why a case was registered after two days and sought the Collector's transfer.
The AIADMK candidate is P Saroja.