Addressing a rally in Mumbai, the Bharatiya Janata Party leader said the Congress will not get seats in double digits in any state.
"The defeat awaiting the Congress is historic. They have not seen such a defeat in any election earlier," Modi said.
"I can tell you that in several states, neither the Congress nor its allies will open their account. In no state will they touch double digits," he said.
Modi made an impassioned plea to the youths to vote for the party "to secure their future".
"This is the age when they decide their entire future and plan out their lives. They must get a strong government which works in their interest. I appeal to all youths to go out and vote for a strong government," Modi said.
Lashing out at the Congress, Modi said it had promised to provide 10 crore jobs before the 2009 polls, but later betrayed the people of the country.
"In the six years of the Atal Bihari Vajpayee government at the centre, the NDA provided 6.5 crore new jobs," Modi said.
He said whenever he raised issues of the youths, jobs for unemployed, women's security or anything concerning the country, the Congress turned around and asked: "But what about secularism?"
Modi accused the UPA of raising the issue of secularism as it has nothing else to discuss. "Nobody is ready or interested in listening to them anymore."
In a dig at Congress vice president Rahul Gandhi, Modi said: "Rahul says Congress is a thought... I say Congress is in a dilemma."
Earlier, addressing a rally in nearby Kalyan, Modi said the Congress was pursuing a single-point agenda - "Stop Modi at any cost".
He said the Congress-led UPA had promised to make India "slum-free" in five years, provide 10 crore jobs and control inflation.
"Has all this happened? The rulers in Delhi must reply, but they are keeping quiet. They have betrayed the people of the country. Instead, they are asking Modi to give replies," the Gujarat chief minister said as the crowds cheered enthusiastically.
In Hardoi in Uttar Pradesh, Modi promised all corrupt leaders would have to face trial if he is voted to power.
"I will not spare anyone who is corrupt or has a criminal background," he told the gathering, which roared in approval.
He said he will ask the Supreme Court to fast-track cases against corrupt public representatives.
He blamed the Congress for many ills plaguing the country, and also took a dig at Sonia and Rahul Gandhi, saying the mother-son duo has destroyed India.
Modi said Samajwadi Party supremo Mulayam Singh Yadav and his son and state Chief Minister Akhilesh Yadav were out to destroy Uttar Pradesh. He urged the people to send as many BJP leaders to the Lok Sabha as they can.
"Delhi mein baithi hai maa-bete ki sarkar aur rajya mein baap-bete ki sarkar, aur dono hi kar rahe hain satyanaash (The mother-son government in Delhi and father-son regime in the state are spelling disaster)," Modi said.
At another rally in Etah, Modi replied to Rural Development Minister Jairam Ramesh who said there was no Modi wave in the country but only Modi poison.
"I accept the allegations but the venom is for the thieves and for the corrupt politicians just to destroy them. This venom will only bring purification," Modi said.
In Mathura, Modi promised to develop tourism.
"Without Yamuna, no mention of Lord Krishna is complete. But see what they have done to the Yamuna. It's an insult," he said.