Stocks closed Tuesday's seesaw session lower as investors remained focused on "fiscal cliff" concerns.
An impending debate in Congress over solving the nation's budget problems kept investors from making aggressive bets.
Equities have been pressured in recent sessions by worries over the cliff - a series of budget cuts and tax hikes that begin to take effect in the new year. Market participants worry that if no deal is reached to avoid going over the cliff, the economy could fall back into recession.
Concerns over the fiscal discussions contributed to the S&P's losses last week, the worst week for the index since June. On Monday, the index staged a modest rebound but only ended up 0.1 percent, off its highs of the session.
"Stocks will be stuck where they are until we get some kind of resolution on this, and if we don't get something done, people will be even more disenchanted with equities than they are now," said Art Hogan, managing director of Lazard Capital Markets in New York.
Home improvement retailer Home Depot reported earnings that beat expectations and raised its outlook.
"Home Depot has two things going for it - an improvement in the housing sector and the rebuilding efforts after Hurricane Sandy," Hogan said. "That's a backdrop where the company is very well positioned."
The S&P index hovered around its 200-day moving average after last week, closing below the level for the first time in five months. An extended run below it could signal further losses ahead.
The S&P 500 is still up about 10 percent for 2012, despite losses in recent weeks. The Nasdaq has fallen for five straight weeks.
The executive most widely tipped to be the next chief executive of Microsoft Corp, Steven Sinofsky, has left the world's largest software maker barely two weeks after launching the flagship Windows 8, as CEO Steve Ballmer moved to tighten his grip on the company. The company's share price sank.
European shares fell as Greece's international lenders gave the country more time to fix its budget, though they didn't disburse the aid Greece had hoped to use to refinance 5 billion euros of its debt pile by Friday.
U.S. stocks closed little changed Monday, with investors limiting bets ahead of the fiscal cliff negotiations. Volume was light, with the U.S. bond market and government offices closed for Veterans Day.
Reuters contributed to this report.
