Key Indian equity indices on Monday danced to the tunes of the assembly polls results of Gujarat and Himachal Pradesh to finally close with gains after swinging from the extreme negative to the positive.

Amid much volatility, the S&P BSE Sensex oscillated within a range of over 1,200 points, and the NSE Nifty50 of over 300 points, on an intra-day basis and trimmed some gains as investors' sentiments were on tenterhooks with counting trends in Assembly polls showing a reduced tally for BJP in Gujarat during late afternoon.

On a closing basis, the wider Nifty50 of the National Stock Exchange (NSE) rose by 55.50 points or 0.54 per cent at 10,388.75 points.

The barometer 30-scrip Sensitive Index (Sensex) of the BSE, which plunged almost 800 points for a fraction of a second during opening trade, closed at 33,601.68 points -- up 138.71 points or 0.41 per cent -- from its previous close.

The BSE market breadth remained bullish with 1,437 advancing stocks as compared to 1,209 declines.

"Markets ended higher on Monday after a very weak opening. The Nifty bounced back sharply as the news came out that the BJP won for a sixth straight term in Gujarat and will replace Congress rule to form government in Himachal Pradesh," Deepak Jasani, Head, Retail Research, HDFC Securities, told IANS.

"Positive cues from global markets also boosted the market sentiments. Sectorally, the top gainers were the PSU banks, metal, pharma and auto indices, while the top loser was the realty index," he added.

On the currency front, the Indian rupee weakened by 20 paise to close at 64.24 against the US dollar from its previous close at 64.04.

"Overall it was a very exciting trading session. Going forward, outlook remains to be positive with focus on housing, cement, infrastructure and metal stocks," said Anita Gandhi, Whole Time Director, Arihant Capital Markets.

"The structural bull market sentiment will continue, however some yearend profit taking by FIIs (foreign institutional investors) cannot be ruled out," Gandhi added.

All the sub-indices of the BSE ended in the positive territory barring the realty and energy indices.

The BSE S&P auto index edged higher by 309 points, followed by metal index by 254.45 points and consumer durables index by 206.84 points.

On the other hand, the S&P BSE realty index fell by mere 6.80 points and energy index by 4.78 points.

Vinod Nair, Head of Research, Geojit Financial Services, said: "Market recovered from the initial disruption after a clear victory for government in Gujarat and Himachal Pradesh state election. Triggers like earnings season and global market movement will be closely watched for any earnings upgrade and US tax reform for the direction."

Major Sensex gainers on Monday were: Mahindra and Mahindra, up 2.71 per cent at Rs 1,522.85; Sun Pharma, up 2.06 per cent at Rs 528.85; State Bank of India, up 1.97 per cent at Rs 318.90; Wipro, up 1.90 per cent at Rs 295.30; and ICICI Bank, up 1.78 per cent at Rs 308.85.

Major Sensex losers were: Yes Bank, down 1.23 per cent at Rs 312.15; Coal India, down 1.11 per cent at Rs 268.05; Infosys, down 0.79 per cent at Rs 1,015.35; ITC, down 0.62 per cent at Rs 263.10; and Kotak Bank, down 0.53 per cent at Rs 1,023.55.