He, however, stopped short of demanding resignation of Akhilesh Yadav government which came to power in 2012 after Samajwadi Party won 225 seats in the 403-member Assembly.
BJP bagged 73 out of 80 Lok Sabha seats in UP whereas Samajwadi Party was reduced to five seats which were won by Mulayam Singh Yadav and his family members. Maywati-led BSP was unable to open its account.
"I am not surprised by the results. This is not unexpected for me. I knew that this can happen and I have been predicting this. Whenever people asked me about how many seats we will win, I always said that there could be a clean sweep.
The barriers of caste have been broken in this election," Mishra, who defeated Niyaz Ahmed of BSP in Deoria, told PTI. UP has not seen a BJP government since 2000-2002 when Rajnath Singh was the chief minister.
Mishra gives entire credit to Narendra Modi's charismatic leadership for the party's revival. "Modi has developed acceptability among masses which resulted in credibility.
People have started to believe that all will be well if he comes into power. I haven't seen such successful election rallies in my life. Definitely, all credit goes to his charisma," said the 73-year-old leader When asked if he feels that Akhilesh Yadav government should resign on moral grounds after this humiliating defeat, he said that it is SP's internal matter.
Earlier, senior party leader Kalyan Singh has demanded resignation of Akhilesh government. "I don't think it is right to ask for his resignation as they have full majority in assembly.
As far as resigning on moral grounds is concerned, it is their internal matter. Chief Minister should decide on this but one thing is sure that this is SP's most humiliating defeat since its establishment," he said.
Mishra alleged that SP befooled people of UP while BSP supremo Mayawati lost due to "her arrogance".
"SP tried to make a fool of people especially after Muzaffarnagar riots where they tried to conceal the real situation. People, however, observed this minutely and realised that SP's intention is to create rift between Hindus and Muslims," said Mishra. He also accused SP of promoting appeasement politics in the state.
"People realised in this election that SP makes tall claims but does not believe in development. They distribute laptops to people from one specific community. Appeasement has been their policy but it boomeranged this time. SP is responsible for the present abysmal condition of farmers be it sugarcane growers or others," he said.
"There have been several disrespectful statements from SP leaders during elections. Mulayam Singh was against harsh punishment for rapists that resulted in anger among women voters," he said.
He did not spare BSP supremo Mayawati and said her "ego let down her party badly". "BSP has become one-woman party. Mayawati was complacent about her vote bank but people of UP have brought both the parties to the ground," he said.
When asked about the future of political parties in UP, he said, "BJP's comeback is inevitable now".
"I don't want to predict about political equations in future but I am sure that no one can stop BJP now. Modi led government at the Centre will provide good governance and development and after witnessing that people of UP will also vote for a change at state level," he added.