His appeal on Twitter comes a day after opposition parties raised concerns over reports of alleged tampering of EVMs and asked the Election Commission to ensure transparency in counting.
Gandhi asked the workers to believe in themselves and the Congress.
"The next 24 hours are very crucial. Stay alert and vigilant. Don't be scared. You are fighting for the truth. Don't be disheartened by the propaganda of fake exit polls. Believe in yourself and the Congress. Your hard work will not go to waste. Jai Hind," he said in a tweet in Hindi.
On Monday, Congress general secretary Priyanka Gandhi Vadra issued a similar message, asking party workers to not be disheartened by "rumours" and exit poll results. She also urged them to be alert at their respective strong rooms and counting centres.
Issuing a recorded audio message for Congress workers, she said they should not fall prey to "rumours and exit poll trends which are being promoted to undermine the spirits of Congress persons".
"Don't be disheartened by rumours and exit polls. These are crafted to undermine your spirits. Because of all this your alertness becomes all the more important. Be on your guard in strong rooms and counting centres. We are sure our and your hard work will bear fruit," Priyanka Gandhi said in the message.
After the exit polls on Sunday predicted a sweep by the National Democratic Alliance, the Congress leadership including President Rahul Gandhi have been quiet on social media. Many of the Congress leaders say one should not jump the gun and wait for official results on May 23.
(With agency inputs)