A key part of the strategy was to stop targeting Prime Minister Narendra Modi.
One done, two more to go. Election strategist Prashant Kishor on Tuesday logged another satisfied client, Arvind Kejriwal, whose Aam Aadmi Party (AAP) won the Delhi election with a giant majority.
Next year, he has the tougher job of helping Mamata Banerjee, who has already been bruised in the national election, and DMK's MK Stalin.
"Thank you Delhi for standing up to protect the soul of India," tweeted Mr Kishor, who had been working with Mr Kejriwal for almost six months.
For Mr Kishor, Tuesday's election result followed personal turmoil. He was sacked by his political mentor, Nitish Kumar, for needling him on the alliance with the BJP and raising tough questions on whether he supported the citizenship law and the National Register of Citizens (NRC).
So this victory was not just vindication but also a message to Home Minister and senior BJP leader Amit Shah, as well as Nitish Kumar, ahead of the Bihar election later this year.
Sources say after signing Mr Kejriwal on, the only advice he offered to the AAP chief was to drop the confrontationist attitude and rebrand himself as the development man. To achieve that, Mr Kejriwal focused on the delivery of promises like CCTVs and free bus rides.
A key part of the strategy was to stop targeting Prime Minister Narendra Modi. The argument was that a lot of BJP voters would vote for AAP in assembly elections, so there was no point antagonising them.
Once the elections were announced, Mr Kejriwal's report card was ready, which was delivered to 25,000 homes in every constituency. This was followed by 15,000 personalised letters to the influential voters who mattered the most. Once Mr Kejriwal had the lead and his personal ratings started going up, his guarantee for five years really caught the BJP off guard.
But Mr Kishor knew that with the BJP, the game could easily go to super overs as Amit Shah and PM Modi are known to be thorough. Once Amit Shah came forward armed with 300 MPs, the entire cabinet and all chief ministers and former chief ministers (including Nitish Kumar), it was clear that victory would be sweet and rewarding.
As the politics of polarisation started dominating headlines, chanting the Hanuman Chalisa was added to Mr Kejriwal's to-do list. The moment a BJP MP called Mr Kejriwal a "terrorist", a protest march was planned.
And on the day the central government announced a new trust to oversee the building of a Ram temple at Ayodhya, sources say, a plan was made and all the newspapers were given an interview so that the AAP chief snagged prominent space the next day.
In Delhi, Mr Kishor knew that the "bijli-paani" waivers were working in favour of AAP. It will be a tougher task in Bengal and Tamil Nadu, which vote next year in April.