Amit Shah, elected the BJP president for a full three years on Sunday, faces an uphill task as four major states go to the polls this year - and he will have to prove that the electoral setbacks of 2015 were an aberration. The Bharatiya Janata Party's rout in Delhi and defeat in Bihar last year are widely seen as having dented the image of Shah, 51 -- as a general who always leads his army to victory. Shah, who took charge of the party in August 2014 from now Home Minister Rajnath Singh, was widely lauded for the way he oversaw the BJP's massive win in Uttar Pradesh in the Lok Sabha election. He was also credited for the BJP wins in the later Maharashtra, Haryana, Jharkhand and Jammu and Kashmir assembly polls. But the Bihar defeat ignited a revolt against Shah's working style by BJP veterans including L.K. Advani and Murli Manohar Joshi, who on Sunday kept away from the event where he was elected the party president. BJP leaders who have worked with him closely say Shah, a confidant of Prime Minister Narendra Modi, has his strengths and weaknesses. "Undoubtedly, Amit Shah is a master strategist and has a long term vision for the party. But he will have to change his working style. Rather than neglecting senior leaders, he will have to re-engage with them," one party leader told media persons on the conditions of anonymity. Shah's real test will come when West Bengal, Pudduchery, Assam, Tamil Nadu and Kerala elect new assemblies in 2016. Uttar Pradesh and Punjab are set for elections in 2017. In Assam, the BJP is making a determined bid to snatch power from a weakened Congress. But the saffron party does not seem to have much of an appeal in the other four places. But Shah is determined to make a mark in West Bengal and open the BJP's account in Kerala, the only major state where it has never won either an assembly or a Lok Sabha seat. The BJP does have a following in Tamil Nadu but is unlikely to upset its relationship with Chief Minister J. Jayalalithaa. Puducherry is not viewed as a major state politically. To win in 2016, Shah, credited with making the BJP the world's largest political party with over 11 crore members, will have to re-energize party cadres after the morale-shattering defeats of Delhi and Bihar. While Shah is said to have a perfect equation with Modi and senior party leaders, BJP sources say this is not so with many others, particularly the second-rung leadership. "His manner of speaking can at times put off those used to the more suave Advani and Rajnath Singh," another party leader said. There was a time when the BJP -- "the party with a difference" -- prided on knowing what people felt because of its cadre strength. Under Shah's leadership, some complain the BJP is run more like a corporate. Modi had handpicked Shah to take charge of Uttar Pradesh in the 2014 Lok Sabha election. Modi himself contested both from Varanasi in Uttar Pradesh and Vadodara in Gujarat, won from both, but retained the Varanasi seat. Shah picked candidates in Uttar Pradesh with a determination to win. In the end, the party got a whopping 71 of the 80 Lok Sabha seats. Ally Apna Dal got two more seats. After that, Shah, anointed the BJP president, led it to victory in Maharashtra even after snapping ties with long-time ally Shiv Sena. It was swept to power in Haryana though it had never won even 10 seats. Jharkhand fell into the BJP kitty, and it took office in Jammu and Kashmir - though as a junior ally - in the country's only Muslim-majority state. 2016 will show if Shah still has his winning credentials in tact.