Rajnath Singh formally took over the reins of the Hindu nationalist Bharatiya Janata Party, or BJP, on Monday, a year and a half after the party unexpectedly lost power in general elections. He replaces Lal Krishna Advani.
The 55-year-old regional politician says his aim is to consolidate the party and make it stronger.
But senior BJP leaders, including former Prime Minister Atal Behari Vajpayee, warn that this could pose a challenge for Mr. Singh.
Mr. Vajpayee says the new BJP president is inheriting a crown of thorns.
Political analysts agree with that assessment. They say Mr. Singh takes over as the party is beset with problems.
The BJP's 2004 electoral loss triggered a loss of morale from which it has yet to recover. In recent months, it has been plagued with internal dissensions and squabbles, a corruption scandal that forced the resignation of six of its lawmakers, and dwindling support in some of its bastions.
But the party faces an even greater dilemma as it tries to decide whether to pitch itself as a moderate force in Indian politics, or move closer to its hard-line Hindu ideological mentors.
Independent political analyst Mahesh Rangarajan says the new leader will have to resolve what direction the country's main opposition party takes.
"It has to be very clear about what kind of opposition it wants to be," he said. "Is it going to fine tune the core ideological message of emphasizing the Hinduness of India as many of its ideologues would like, or would it like to play the role of a normal opposition party in any democracy to voice the grievances of large sections of the people?"
The change of guard also signals a shift to a younger leadership, and the end of an era when the party was dominated by two of its best-known leaders - Mr. Vajpayee and Mr. Advani. The two men were instrumental in the party's formation 25 years ago, and its subsequent rise to prominence.
Mr. Vajpayee, now 81 years old, has announced his intentions to retire from active politics, although he will continue to head a political alliance led by the BJP.
The 77-year-old Mr. Advani, who was forced out of his leadership role because of comments he made praising rival Pakistan's founder, will continue to play an active role in BJP. But at the same time, analysts say younger leaders are expected to assume a greater role in the party in the coming years. However, this could throw up new challenges for the BJP as it may trigger a struggle among the second-rung leaders for control of the party.