document: Thethe Dow Jones closed 0.4% higher at 18,332.43, the S&P 500 rose 0.4% at 2,139.53 while the tech-heavy Nasdaq jumped 0.5% to 5,193.49.
  Analysts said the number of shares being traded was lower than normal.
  Banks are reported to have put extra staff on duty in case of volatility.
  "It doesn't take much in order to move the prices," said Peter Jankovskis, co-chief investment officer at OakBrook Investments.
  Despite fears over the outcome of what is expected to be a tight race between Hillary Clinton and Donald Trump, analysts said investors would be relieved that the long period of uncertainty had come to an end.
  "No matter who is elected, it will end a tremendous divide and return focus to earnings and all the fundamentals that have been pushed to the sidelines in recent weeks," said Rick Meckler, president of investment firm LibertyView Capital Management.
  The three main US stock indexes saw their strongest rise in over eight months on Monday after the FBI announced it would not press criminal charges against Clinton for her use of a private email server.
  The most dramatic stock movement in the US was car hire firm Hertz, which fell over 20% after the company slashed its full-year profit forecast.
summary: US shares have risen slightly, erasing earlier losses, but investors remain wary ahead of the US presidential election results.