Investors also were still digesting Friday's weaker-than-expected U.S. payrolls report for April, which sparked a selloff and produced a weekly loss of 2.4 percent for the S&P 500 -- its worst weekly performance of the year. Greeks voted out their ruling parties in elections on Sunday, dealing a blow to the fragile political consensus that had kept Europe's currency bloc intact through more than two years of crisis. The country's banking index slid 16 percent. There's chaos in Greece, and being against the deal that was already agreed upon is almost like progress being set back a year and a half, said Scott Freeze, president of StreetOne Financial in Huntington Valley, Pennsylvania. The big concern is that this sets us up for substantial financial losses. Worries over the debt crisis have helped to drive weakness in U.S. equities in recent months with investors concerned about its effects on global growth and corporate profits. Some bearish U.S. economic data, most notably the payrolls report, have exacerbated fears that growth may be stalling.
In France, Socialist candidate Francois Hollande won the presidency over incumbent Nicolas Sarkozy, raising pressure on Germany to pursue a more growth-oriented approach to the regional crisis.
S&P 500 futures fell 6.7 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures lost 56 points, and Nasdaq 100 futures dropped 10.5 points.
Earnings season is winding down, and of the 415 S&P 500 components reporting as of Friday morning, 67.5 percent have exceeded estimates, according to Thomson Reuters data. That represents a sharp decline from the start of earnings season, when more than 80 percent beat expectations. Cognizant Technologies Solutions Corp dropped 9.8 percent to $62.80 in premarket trading after cutting its full-year profit and revenue outlook, citing low demand.
Tyson Foods Inc reported second-quarter earnings that rose from the prior year on prices increases. Satellite imagery company DigitalGlobe Inc rejected a $792 million takeover offer from rival GeoEye Inc on Sunday, saying the hostile bid substantially undervalued the company and its prospects. With last week's decline, the S&P 500's 3.5 percent pop from an April closing low to a May closing high has largely been erased. The market has found support around the April closing low of 1,358.59 in the past, but a breach there could take it back to 1,340. The benchmark index is moving away from strong resistance at 1,400 after failing to make a convincing move above it.