(Recasts, adds fresh quote from Bangalore voter)
By Ashutosh Pandey and Swetha Gopinath
BANGALORE, April 17 (Reuters) - India called a quarter of its 815 million voters to polls on Thursday, the biggest day of its staggered election, in areas ranging from Himalayan passes to a southern IT hub and western sugarcane farms.
The country is now over halfway through its nine days of voting for a new parliament in the world's biggest ever election, with the ruling Congress party struggling to hold ground against the Hindu nationalist opposition.
Narendra Modi, the opposition Bharatiya Janata Party's (BJP) candidate for prime minister, has been wooing voters with promises to rouse India's economy from its slowest growth in a decade and create jobs for its booming young population.
A decision by the Election Commission to reprimand a senior Modi aide for making speeches deemed to stir tensions with minority Muslims underlined critics' assertions that the party is a divisive force.
But in the latest large opinion poll, taken in the first week of April, the BJP and its allies were forecast to win a narrow majority in the 543-seat lower house of parliament, compared with previous surveys predicting that they would fall short.
"Modi could be the change we need," said software engineer Murali Mohan, after casting his vote in a suburb of Bangalore, the centre of India's outsourcing sector and the capital of the lush southern state of Karnataka.
"I want to see constructive work, economic development in this country," said Mohan, 39.
Voting took place in 120 constituencies across 12 states, with election materials airlifted to parts of the fractious Himalayan state of Jammu and Kashmir, while mobile polling stations in vans were used in the deserts of Rajasthan.
One rural constituency in the western state of Maharashtra had three candidates with the same name, an apparent use of the "clone candidates" strategy that parties sometimes employ to confuse voters and split support for rivals.
Voting runs until May 12 and results are due on May 16.
MEMORIES OF RIOTS
Modi's image remains tarnished by Hindu-Muslim riots in Gujarat, the western state where he is chief minister, on his watch 12 years ago. More than 1,000 people, most of them Muslims, were killed in the violence.
Modi denies accusations that he failed to stop the riots and a Supreme Court inquiry found he had no case to answer. In an interview with ANI television news on Wednesday, Modi accused reporters of smearing him over the riots.
"People have forgotten what Modi did to people of this country. I think saving people's lives is more important than development," said Shafina Khan, a 21-year-old Muslim teacher in Kamshet village in Maharashtra who voted for the Nationalist Congress Party, a Congress ally.
Election authorities on Wednesday issued an order rebuking Amit Shah, who runs the BJP's campaign in Uttar Pradesh, India's most populous state, over his speeches.
"The Election Commission is the supreme body and I abide by its decision," Shah said on his Twitter account after the order.
The commission last week banned Shah from election rallies and meetings. The latest order did not mention the ban, or what new restrictions might now be sought.
TECH BILLIONAIRES AND ESTRANGED COUSINS
Congress, led by the Nehru-Gandhi dynasty, is forecast to suffer its worst-ever defeat after a decade in power due to the economic slowdown, high inflation and repeated graft scandals. The party has ruled India for more than 50 of its 67 years of independence.
A former media adviser and a former coal secretary have both released books in recent days that paint Prime Minister Manmohan Singh as a well-intentioned but weak figure who answers only to party president Sonia Gandhi.
"It's only a dynasty, like previously we had kings ruling," said P.V. Padmanabhan, a 79-year-old retired electricity board official who has voted in every Indian election, and was lining up to vote at the eastern Bangalore polling station.
"They have to give it to somebody else. (Leaders) should not only come from Nehru's family."
Indian elections are notoriously hard to forecast due to the diverse electorate and a parliamentary system in which local candidates hold great sway. Opinion polls wrongly predicted a victory for a BJP-led alliance in elections in 2004 and underestimated Congress's winning margin in 2009.
Voter turnout has averaged 68 percent so far, the Election Commission said on Wednesday, versus 58 percent across the whole election in 2009.
"It is because of the people's unrest against the establishment," Nitin Gadkari, a BJP leader and the party's former president, told Reuters. (Additional reporting by Nandita Bose in KAMSHET, Jatindra Dash in BHUBANESHWAR, Sharat Pradhan in LUCKNOW, Fayaz Bukhari in SRINAGAR, Rohit T.K. in BANGALORE and Aditya Kalra in NEW DELHI; Writing by Shyamantha Asokan; Editing by Douglas Busvine and Ruth Pitchford)