MUMBAI (REUTERS) - Indian markets are so confident the opposition party led by Narendra Modi will win the country's elections that brokers fear anything short of a decisive victory could spark the worst sell-off in years.
Shares hit a record high on Friday as opinion polls pointed to a sweeping win for the Bharatiya Janata Party, seen as more business friendly than the rival Congress party.
But caution about the vote results may prove warranted. Most investors were caught off guard in the past two general elections - in 2004 and 2009 - as opinion polls got it badly wrong.
Now some precautionary moves are being made. Customers say at least four brokerages have raised margin requirements due to concern there could be intense volatility after election results are unveiled on May 16.
The stock market regulator has asked exchanges to test their trading systems, according to an agency official, especially new mechanisms put in place last year to deal with market volatility. The Securities and Exchange Board of India (Sebi) did not reply to a written request for comment.
A surprise could knock both shares and the rupee. The gains stem from the assumption the BJP and its National Democratic Alliance (NDA) will win a majority, or near it, making Modi India's prime minister.
From Sept. 13 - the day the BJP nominated Modi as its prime ministerial candidate - through Friday, the National Stock Exchange, India's biggest bourse, surged 17 per cent, compared with only a 4 per cent gain for the MSCI Asia-Pacific index excluding Japan. On Friday, the NSE index rose as much as 3.2 per cent, hitting a record high of 6,871.35.
Should BJP do poorly in the vote and Mr Modi not become prime minister, some analysts predict shares could plunge 8 to 10 per cent in one day, and up to 20 per cent in the aftermath. That would roughly match what happened in 2004, when investors were shocked that the BJP didn't win the election. The NSE index fell 12.2 per cent in one day, and 19 per cent over two.
Ritu Jain, managing director of investment bank Eos Capital Advisors in Mumbai, said the recent rally in Indian shares "has been largely in anticipation of NDA coming to power with a majority or near to majority."
"In the event of NDA not coming to power, markets can correct by about 15 per cent or a little more."
The BJP has long been seen by markets as being more investor-friendly than the Congress party, spurring hopes Mr Modi will revive an economy growing at its slowest pace in a decade. The hopes have sent sectors such as infrastructure and banks sharply higher. Foreign investors have also bought in heavily, and now own a record 22 per cent of companies listed on the NSE, according to Morgan Stanley data, after buying a net US$20.1 billion last year (S$ 25 billion) and about US$4.3 billion so far in 2014.