Already blamed for record oil prices, Hurricane Ivan blew away back-to-school business at many of the nation's big chain stores -- and maybe enough jobs to change the outcome of the presidential election.

Today's September retail report showed sales growth slowed for the third month in a row, which is a worrisome trend when the U.S. economy depends so heavily on consumers.

Part of the slowdown was attributed directly to Ivan -- all the plywood, tarps and generators that were sold did not make up for the massive amounts of business lost because of Ivan and the other hurricanes that tore through Florida.

Part was due to collateral damage from Ivan, which cut off-shore oil production in the Gulf of Mexico, thus helping drive up prices. High-priced gasoline and heating fuels, in turn, are blamed for bleeding family budgets of cash that might otherwise have been spent at Wal-Mart, Target or other chain stores.

Ivan's impact on oil prices and chain store sales alone was enough to set back the market, but Wall Street also was worried that Ivan's impact will be felt again Friday when the government issues its last unemployment report before the November voting.

Economists surveyed by Bloomberg News are predicting the data will show September's hurricanes blew away as many as 100,000 jobs. If the report is as bad as expected, it may help determine the agenda for the second presidential debate, which is Friday night, and perhaps even influence the outcome of the election.

Adding to Wall Street's unusual woes today was a medical research article suggesting that Merck's arthritis drug Vioxx may not be the only medicine that can increase the risk of heart problems and stroke. Merck withdrew the drug last week after a study showed a problem. But other drugs in the same class, known as COX-2 inhibitors, may produce the same cardiovascular problems if data on their users is examined closely, doctors are warning.

Without waiting for any actual studies, stock traders bailed out of Pfizer, the maker of Celebrex, the chief competitor to Vioxx. Pfizer stock fell about 4 percent today, and Merck shares continued to slide, ending the day worth one-third less than the were before Merck pulled Vioxx off the market.

Other drug and biotech stocks also suffered as the market declined across the board.

The Dow Jones industrial average fell almost 115 points to 10,125.40.

The Standard & Poor's 500 stock index retreated more than 11 points to 1,130.65.

The Nasdaq Stock Market composite index ended its seven-day winning streak with a loss of almost 23 points, closing at 1,948.52.