With Aam Aadmi Party (AAP) leaders flocking to Punjab as the Assembly poll campaign heats up, the ruling Congress has now decided to bring the fight to its rival's home turf, Delhi. In a tit-for-tat move, Punjab Congress chief Navjot Singh Sidhu today joined a dharna by guest teachers outside Delhi Chief Minister and AAP convener Arvind Kejriwal's residence in demand of regularisation.