AHMEDABAD, India: Indian Prime Minister Narendra Modi's home state of Gujarat began voting on Saturday, in a key electoral test of his popularity after a series of controversial economic reforms.

Voters, with their election cards in hand, started lining up at polling booths early in the morning in Gujarat where Modi's Hindu nationalist Bharatiya Janata Party (BJP) has held power for 22 years.

"Urging all those voting today to turnout in record numbers and vote. I particularly call upon youngsters to exercise their franchise," Modi, who forged his political career in Gujarat, tweeted early Saturday.

Modi built his reputation as an economic reformer in Gujarat which boomed under his rule, attracting investments from around the globe.

But his recent reforms -- a new national tax and a shock currency ban to fight graft -- have hit India's growth and hurt the very constituency of traders and small business owners who were his biggest supporters in the western state, polls found.

Experts say this election is a serious challenge to Modi as his rivals ride a wave of discontent over the stuttering economy, adding that voter anger over the reforms and a desire for change could boost the flagging fortunes of the opposition Congress Party.

The Congress campaign has been spearheaded by Rahul Gandhi -- the man likely to challenge Modi for premiership at the next general election in 2019.

The election is seen as a chance for Gandhi to finally prove his mettle before he is named president of the party his mother Sonia has led for more than two decades.

Another threat to Modi's dominance comes from two prominent groups -- the Patidars, who make up almost 14 percent of Gujarat's 43 million voters, and the low-caste Dalit community.

The Patidars, a relatively well-off caste group comprising farmers and traders who came out in force to support Modi in previous polls, have rocked the state with demands for preferential access to government jobs and education.

A little over 21 million voters are eligible to cast their ballots till 5:00 pm local time (1130 GMT) in the first stage of the election on Saturday, with over 30 percent turnout reported by mid afternoon.

Nearly 1,000 candidates are vying for power in 89 constituencies across 19 districts of Gujarat, according to the Election Commission of India.

The next stage of voting is on December 14.-AFP