On a day when AAP leader Arvind Kejriwal took oath as the eighth chief minister of Delhi, senior BJP leader M Venkaiah Naidu today said that the saffron party had made a tactical mistake of not going in for the Assembly poll in Delhi immediately after the Lok Sabha election last year.br br "We made a tactical mistake. I have no hesitation in accepting it. After the Lok Sabha election, we could have gone for an Assembly election immediately, we would have won hands down in Delhi. But a lot of time has passed," Naidu told reporters here.