The BSE Sensex was trading 304 points up at 21,013 points, a short while ago. It regained psychological 21,000 level by surging 439 points to trade at 21,148 in the opening trade on heavy fund inflows amidst exit polls forecasting good show by the BJP in state assembly elections. The 30-share index had lost 189 points in the previous two sessions. The NSE Nifty was also trading 95 points up at 6,256 points, a short while ago.