S&P 500 Leaders and Laggards: ABK AW

The S&P 500 was nearly unchanged, rising 0.11 points to close at 1,360.14.

The top gainer was insurer Ambac Financial Group Inc., which jumped 19 cents, or 9.1 percent, to $2.29.

Gamestop rose $3.43, or 7.7 percent, to $47.94 after Goldman's Robert Higginbotham raised the stock from "Sell." He said the stock's significant decline in the last two months now accurately reflects the weakness in the broader gaming sector, warranting the higher rating.

MGIC Investment Corp. advanced 63 cents, or 6.4 percent, to $10.48 after the mortgage insurer said it reached a reinsurance agreement with an affiliate of HCC Insurance Holdings Inc. that covers up to $50 billion in new insurance between April 1, 2008 and Dec. 31 2010.

Among the decliners, Allied Waste Industries Inc. shed $1.16, or 7.7 percent, to $13.84 after the solid waste management company said it was in talks to buy competitor Republic Services Inc. The deal would give Allied Waste shareholders 0.45 shares of Republic common stock for each share of Allied Waste stock.

Textron Inc. fell $3.76, or 6.5 percent, to $54.42 after the industrial conglomerate cut its second-quarter earnings forecast on lower-than-expected earnings in its finance unit.

Hershey Co. shed $2.46, or 6.4 percent, to $35.87. On Sunday, the chairman of the trust that holds a controlling interest in the confectioner wrote in a newspaper editorial that the trust has no intention of selling the company.