Among the 10 industry groups in the S&P 500 index, financial stocks and energy companies fell the most.
Banks figure to face tougher regulation in a second Obama term than they would have under Romney. JPMorgan Chase fell 5.6 percent, Citigroup 6.3 percent, Bank of America 7.1 percent, Goldman Sachs 6.6 percent and Morgan Stanley 8.6 percent.
The biggest losers were coal companies, which had hoped that a Romney administration would loosen mine safety and pollution rules that make it more costly for them to operate. Peabody Energy dived 9.6 percent, Consol Energy 6.1 percent, Alpha Natural Resources 12.2 percent and Arch Coal 12.5 percent.
Oil companies fell less steeply.
Trading also reflected the outcome of ballot measures decided in Tuesday's election. After two states approved the recreational use of marijuana for the first time, Medical Marijuana Inc., a company too small to be listed on major exchanges, surged 22 percent.
Other notable moves included Apple, the world's most valuable company. It fell 3.8 percent to $558.00 and has dropped 20 percent from its all-time high of $705.07, reached Sept. 21.
AP Business Writers Christina Rexrode and Steve Rothwell in New York, Tom Murphy in Indianapolis, Linda Johnson in Trenton, N.J. and Marcy Gordon in Washington contributed to this report.
Daniel Wagner can be reached at www.twitter.com/wagnerreports.
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