US stocks have taken their biggest loss in five months as a healthcare bill backed by President Donald Trump ran into trouble in Congress.
It raised some questions about his agenda of faster economic growth spurred on by lower taxes and cuts in regulations.
Banks plunged as bond yields continued to fall, which will mean lower interest rates on loans.
Transportation companies including airlines, railroads and rental car companies dropped, and so did materials companies such as steel and chemicals makers.
The dollar weakened. Small-company stocks, which stand to benefit the most from Mr Trump's policy proposals of lower taxes and looser regulations, fell more than the rest of the market.
"President Trump promised that this healthcare bill would be signed, sealed, delivered within the first couple of weeks of him taking office," said Jack Ablin, chief investment officer for BMO Capital Markets.
"All this is doing is pushing the rest of the agenda out."
The Standard & Poor's 500 index tumbled 29.45 points, or 1.1%, to 2,344.02. That was its biggest drop since October 11.
The Dow Jones industrial average fell 237.85 points, or 1.1%, to 20,668.01.
The Nasdaq composite surrendered 107.70 points, or 1.8%, to 5,793.83.
The Russell 2000 index of small-company stocks plunged 37.55 points, or 2.7%, to 1,346.55. Four-fifths of the stocks on the New York Stock Exchange fell.
Stocks have fallen for four days in a row, though the previous losses were small.
Tuesday's losses were a reversal of the patterns that have endured since Mr Trump was elected in November, but overall stocks are still sharply higher since then.
On Thursday the House of Representatives is scheduled to vote on the Republican-backed American Health Care Act, and despite support from the president on Tuesday, it is not clear if the House or the Senate will approve the bill.
The administration hopes to get a major tax reform package to Congress by August, and a big infrastructure spending proposal may follow next year.
Banks had their worst day in nine months as bond prices rose.
The yield on the 10-year Treasury note declined to 2.42% from 2.46%.
Bank of America fell 1.42 dollars, or 5.8%, to 23.02 dollars. KeyCorp sank 1.18 dollars, or 6.5%, to 16.90 dollars, the biggest loss in the S&P 500. JPMorgan Chase gave up 2.64 dollars, or 2.9%, to 87.39 dollars.
Still, banks have done far better than the rest of the market since the election.
Among transportation companies, United Continental lost 2.21 dollars, or 3.3%, to 65.28 dollars and railroad operator CSX declined 1.26 dollars, or 2.7%, to 45.62 dollars. Hertz Global skidded 1.86 dollars, or 8.7%, to 19.40 dollars. Companies that make steel, chemicals, and other basic materials also slid. AK Steel plunged 86 cents, or 10.4%, to 7.51 dollars and US Steel lost 3.34 dollars, or 9%, to 33.76 dollars.
The price of copper also dropped. The metal's price tends to rise when investors are more optimistic about the economy, and copper has risen 14% over the last year. It sank five cents, or 1.8%, to 2.62 dollars a pound on Tuesday.
Big dividend companies, especially utilities, did well. Investors often buy those stocks when bond yields are falling. Dominion Resources rose 1.38 dollars, or 1.8%, to 78.21 dollars and PPL gained 67 cents, or 1.8%, to 37.47 dollars. Some household goods makers also rose. Jack Daniel's whisky maker Brown-Forman climbed 47 cents, or 1%, to 47.28 dollars.
Kate Warne, an investment strategist for Edward Jones, said investors are taking some profits after the market's long post-election winning streak, but noted that Wall Street is especially eager for the administration's tax reform proposals.
"I think investors see (corporate tax reform) as more important in terms of supporting the stock market even if it's not as important in terms of its effect on the economy" as healthcare, she said.
Food companies fell after General Mills posted a better-than-expected profit but weaker sales. The Cheerios maker faces more competitive pricing and a market that has been shifting demand from processed foods. Its stock dipped 50 cents to 59.76 dollars, and Kellogg shed 1.38 dollars, or 1.8%, to 73.60 dollars. Campbell Soup gave up 1.91 dollars or 3.2%, to 57.09 dollars.
Benchmark US crude lost 88 cents, or 1.8%, to 47.34 dollars a barrel in New York. Brent crude, used to price international oils, closed down 66 cents, or 1.3%, to 50.96 dollars a barrel in London.
The price of gold jumped 12.50 dollars, or 1%, to 1,246.50 dollars an ounce. Silver gained 15 cents to 17.58 dollars an ounce.
In other energy trading, wholesale gasoline lost one cent to 1.61 dollars a gallon. Heating oil dipped one cent to 1.50 dollars a gallon. Natural gas rose five cents, or 1.7%, to 3.09 dollars per 1,000 cubic feet.
The dollar slipped to 111.90 yen from 112.58 yen. The euro rose to 1.0804 dollars from 1.0733 dollars.
The DAX of Germany fell 1.1% and the British FTSE 100 lost 0.6%. France's CAC 40 made big early gains after a debate between the nation's candidates for president, but it finished 0.5% lower. Japan's benchmark Nikkei 225 slipped 0.3%. The Kospi in South Korea rose 1% and in Hong Kong the Hang Seng rose 0.4%.