MUMBAI, Jan 20 (Reuters) - Prime Minister Narendra Modi’s Bharatiya Janata Party (BJP) chose a little-known legislator from India’s poorest state as ​the party’s youngest president on Tuesday, a generational shift ‌in the effort to retain young voters.

Nitin Nabin, 45, takes over from outgoing president ‌J.P. Nadda, 65, months before key state elections, one of them in the eastern state of West Bengal, which the BJP has never won and is strongly focused on.

A five-time lawmaker from the eastern state ⁠of Bihar, Nabin was ‌elected unopposed as the party’s 12th president after Modi and other leaders proposed him.

Hundreds of workers watched at ‍party headquarters in New Delhi as Nabin, his forehead smeared with a vermillion mark and his shoulders wrapped in a scarf with the party symbol, ​took the oath of office before Modi and four past presidents.

"When ‌it comes to the party, I am a worker and he is my boss," Modi, 75, said in his remarks, pointing to Nabin, who will serve a three-year term.

In his speech, Nabin repeatedly praised Modi as a generational leader and urged young people to take an active ⁠part in politics.

More than 40% of ​India’s one billion voters are aged between ​18 and 39, the Election Commission and analysts estimate.

The BJP suffered a shock setback in the 2024 general election as ‍Modi lost his ⁠majority after 10 years in power and had to rely on regional allies to form a government.

But it has since ⁠regained ground, winning critical state and civic body elections. The party and its allies govern ‌19 of India’s 28 states.

(Reporting by Shilpa Jamkhandikar; Editing ‌by YP Rajesh and Clarence Fernandez)