SURAT - India's Aam Aadmi Party (AAP), formed only a decade ago and having claimed power in Delhi and Punjab state, is set to be the biggest gainer in assembly elections in Prime Minister Narendra Modi's home state of Gujarat next month.

AAP boss and Delhi Chief Minister Arvind Kejriwal is known to have national ambitions. A strong showing in Gujarat, a prosperous state of more than 60 million, could indicate whether his party's appeal has widened beyond smaller states ahead of the 2024 general election.

According to a projection by ABP-CVoter, AAP's vote share in Gujurat is expected to rise to 20% from zero five years ago, mainly at the expense of the main opposition Congress party, which dominated Indian politics before being drubbed by Modi's Bharatiya Janata Party (BJP) in the last two general elections.

Seven voters in Gujarat's Surat city, a diamond cutting and polishing hub, told Reuters they had been drawn to AAP's promise to improve education and healthcare - both areas where the party says it has delivered results in Delhi since 2015.

"Ninety-nine per cent I am going to vote for Aam Adam Party," said diamond worker Bharat Patel.

"Many in my personal and professional circles are also going to do the same. I have heard a lot about their work in education and healthcare in Delhi and I feel they deserve a chance."

The Hindu-nationalist BJP has been in power in Gujarat since 1998, with Modi serving as its chief minister for nearly 13 years. Current projections show Congress will stay the second- biggest party in the 182 member-assembly, but that could change.

"It looks like the surge of the Aam Aadmi Party is not going down," Yashwant Deshmukh, founder of polling agency CVoter, told Reuters. "If the trajectory continues, and they end up with a 25-26% vote share, they could trump Congress."

Gujarat will vote in two phases on Dec. 1 and Dec. 5. Results are due on Dec. 8.

AAP, which grew out of an anti-corruption movement in 2012, has been strengthening its presence in Gujarat, including in its second-largest city of Surat.

Early last year, it won 27 of the 120 seats in Surat's municipal elections, emerging as the main contender to the BJP.

Across Surat, large hoardings of the BJP and AAP dominate the streets. With pictures of Modi, the ruling party is underlining the advantages of having a BJP government at the state and nationally.

"How many votes the AAP gets and how many seats it can win remains to be seen," said Virang Bhatt, a Surat-based political analyst. "But the party has certainly managed to create strong visibility and appeal here."

(Writing by Devjyot Ghoshal; Editing by Krishna N. Das and Mark Potter)