Indian shares extended their roll Wednesday, hitting another lifetime high while the rupee traded at a fresh eight-month peak, as investors bet a more business-friendly government will come to power in elections. But some analysts warn expectations that the opposition Hindu nationalist Bharatiya Janata Party (BJP), tipped to win the polls, can turn around India's ailing economy may be a mirage. Much investor optimism over a BJP win rests on belief that Narendra Modi, the conservative chief minister of prosperous Gujarat state, will advocate pro-growth reforms to open up India's still largely closed economy. But "current optimism in our view is going too far," Capital Economics analyst Miguel Chanco said, noting unwieldy coalition politics that hamstrung the current Congress government could constrain the next administration too. Still, opinion polls suggesting the BJP will oust the scandal-tainted Congress in the elections due to kick off next month have pushed business optimism to its highest since 2011, according to business information provider Dun and Bradstreet. The Bombay Stock Exchange's benchmark index rose nearly a fifth of a percent to a new peak of 22,095.30 points Wednesday while the rupee ended the day at 60.14 to the dollar. The rupee is at its highest against the dollar since late July. The rupee crashed against the dollar last year as foreigners headed for the exits on a gloomy economic outlook. But now foreigners are pumping money into Indian markets, investing $2.5 billion in shares in March alone. "If the BJP comes to power, it will be taken as a signal for stability in the economy and stock markets will take it very positively," said Vivek Gupta, research director at CapitalVia Global Research Investment. - Riding popularity wave - Modi, 63, is riding a wave of voter popularity amid disenchantment with Congress under which growth has slumped to 4.7 percent, half its pace during India's boom years. Modi's chances of leading India were widely written off over charges he turned a blind eye to 2002 Gujarat riots that left at least 1,000 people, mainly Muslims -- allegations he has always denied. But Gujarat's reputation as one of India's fastest growing states -- it expanded by nearly 10 percent annually over the last five years -- and its easy investment policies have won him national favour. Investors hope Modi, who has a reputation for quick decisions and clean governance, will be able to replicate his policies nationally and boost growth. But some analysts question the BJP's pro-market credentials as well as the ability of Modi, who has a reputation for being abrasive, to forge a consensus for change in India's faction-ridden populist politics. "Even within the BJP, he has many, many enemies... Getting things done in such an environment and with Mr Modi's personality seems a daunting task," said Jamal Mecklai, head of Mecklai Financial. The BJP opposed moves to open up India's economy while in opposition, fighting such measures as allowing foreign supermarkets into the country Analysts add it is unlikely a BJP government could revive the stalled investment cycle, as India's central government only controls a quarter of the country's investment projects. "Even elsewhere -- roads, railways, etcetera -- solutions will take years," said Credit Suisse economist Neelkanth Mishra in a report calling the elections "much ado about nothing". And there are worries about Modi'shawkish Hindu politics, with fears he could upset the secular landscape in India where Muslims make up around 13 percent of the population. The BJP, and Modi in particular, also have cultivated an image of macho nationalism that has the potential to exacerbate border tensions with traditional foe Pakistan and neighbouring rival China and "roil markets", noted Eurasia Group analyst Anjalika Bardalai.