US stock markets close lower ahead of Greek elections

US main stock indices after previous rally traded lower on Wednesday as investors awaited for the outcome of Greek elections while Moody's and Egan-Jones downgraded Spanish sovereign debt. S&P 500 lost 0.7% or 9.3 points and closed at 1,314.88. Dow Jones Industrial Average fell 0.62% or 77.42 points and finished at 12,496.38. Nasdaq Composite ended 0.86% or 24.46 points down at 2,818.61.