NEW YORK (AP) -- Stocks retreated for a seventh consecutive day on Wednesday, the market's longest decline in five years, as investor worries about the U.S. presidential election continued to weigh on the market.
A steep decline in oil prices also shook investor confidence.
The Dow Jones industrial average lost 77.46 points, or 0.4 percent, to 17,959.64. The Standard & Poor's 500 index lost 13.78 points, or 0.7 percent, to 2,097.94 and the Nasdaq composite fell 48.01 points, or 0.9 percent, to 5,105.57.
The last time the S&P 500 fell for seven straight days was November 2011, during a flare-up of the European sovereign debt crisis.
Like most of the public, investors have their eyes glued to the presidential race, as polls between Hillary Clinton and Donald Trump have tightened. The narrowing in the race has brought more uncertainty. Gold and bond prices have risen. The VIX, a volatility measure dubbed the "fear gauge" for Wall Street, jumped 14 percent on Tuesday to its highest level since June. It was up another 4.4 percent Wednesday.
The Mexican peso, which has become a de facto proxy for Trump's chances to win the election, has fallen steadily against the U.S. dollar since Friday and fell another 1 percent on Wednesday to 19.425 pesos to the dollar. Investors expect that Mexico's economy would be negatively impacted by a Trump administration, which would weaken the peso.
"The lead-up to the U.S. presidential election was always expected to be lively but the events of the last couple of days has seriously taken its toll on investor sentiment," said Craig Erlam, senior market analyst at OANDA.
Meanwhile a report from the Energy Department that showed a significant buildup in crude oil supplies last week weighed heavily on oil and energy prices. Benchmark crude oil sank $1.33 to $45.34 a barrel in New York. Brent crude, the international standard, fell $1.28 at $46.86 a barrel.
Energy stocks were among the biggest decliners in the S&P 500. Pioneer Natural Resources, Marathon Oil and Sempra energy fell 4 percent or more.
Aside from the election cliffhanger, investors parsed through the latest policy statement from the Federal Reserve. While the nation's central bank voted to keep rates at their current level after their two-day meeting, they left the door open to raise rates at their meeting in December. It was expected the Fed would not want to raise rates ahead of the election.
"If we get an unexpected election outcome, the Fed might put any increase on hold. We are not convinced that December is a sure thing," said Brandon Swensen, a portfolio manager and co-head of fixed income trading at RBC Global Asset Management.
The yield on the 10-year Treasury note fell to 1.80 percent from 1.83 percent the day before.
In individual company news, Brocade Communications rose $1.08, or 10 percent, to $12.32 after Broadcom announced it would buy the company for $5.5 billion. Broadcom rose $3.76, or 2.2 percent, to $172.56.
The dollar fell to 103.28 yen from 103.97 yen, while the euro rose to $1.1096 from $1.1062.
In other energy trading, heating oil fell 5 cents to $1.47 a gallon, wholesale gasoline fell 4 cents to $1.45 a gallon and natural gas fell 11 cents to $2.792 per 1,000 cubic feet.
Precious and industrial metals futures closed mostly higher. Gold increased $20.20 to $1,308.20 an ounce, silver climbed 28 cents to $18.69 an ounce and copper was little changed at $2.23 a pound.