US stocks opened sharply lower Monday with the government faced with just four days to resolve the political deadlock over the budget and debt before being forced to default on its bills. After a weekend that saw no progress in talks between the White House and Republicans, five minutes into trade, the Dow Jones Industrial Average was down 76.10 points (0.50 percent) at 15,161.01. The broader S&P 500 lost 8.41 (0.49 percent) to 1,694.79, and the Nasdaq Composite gave up16.27 (0.43 percent) to 3,775.60.