Rashtriya Janata Dal (RJD) leader Tejashwi Yadav on Tuesday made a strong pitch in support of his ‘bade bhai (elder brother)’ and Congress MP Rahul Gandhi, during the ongoing Voter Adhikar Yatra and declared that the Mahagathbandhan (RJD-Cong-Left alliance in Bihar) will work towards making him the next Prime Minister.