U.S. stocks were little changed in a see-saw session that saw light volume on Thursday as investors paused after a four-day rally and ahead of Friday's key payrolls report.

Wall Street stocks initially climbed after the Institute for Supply Management's (ISM) factory activity index stayed above 50, the expansion threshold. But stocks lost altitude by midday.

After dropping more than 17 percent from early July to early August, the S&P 500 is up 9 percent, leaving investors reluctant to place big bets ahead of the government's August labor report, which is expected to show an increase of 75,000 jobs.

You are right in between the two points where the market is uncertain in terms of where we are going, said Marc Pado, U.S. market strategist, Cantor Fitzgerald & Co in San Francisco.

The picture that we are getting not only from (manufacturing) numbers, but the ADP number, the regional Fed surveys and the ISM is that the business community and jobs is not falling backward but has kind of slowed to a snail's pace going forward.

The Dow Jones industrial average <.DJI> gained 6.09 points, or 0.05 percent, to 11,619.62. The Standard & Poor's 500 Index <.SPX> added 0.03 points, or 0.00 percent, to 1,218.92. The Nasdaq Composite Index <.IXIC> tacked on 1.48 points, or 0.06 percent, to 2,580.94.

The benchmark S&P is up more than 5 percent during the four-day rally on increasing hopes for a new stimulus plan from the Federal Reserve at its meeting later in September.

Energy stocks were among the best performers, with Chevron Corp up 1 percent to $99.89, leading the Dow. The S&P energy sector index <.GSPE> rose 0.8 percent.

Ciena Corp jumped 19.1 percent to $14.58, helping to boost the Nasdaq, after the communication equipment maker posted a profit for the first time in three years. The NYSEArca networking index <.NWX> rose 0.9 percent.

U.S. construction spending fell unexpectedly in July as public outlays dropped to their lowest level since December 2006 and private spending also sagged, separate data showed.

Weekly jobless claims declined by 12,000 in the latest week, while nonfarm productivity was weaker than previously thought in the second quarter.

(Reporting by Chuck Mikolajczak; editing by Jeffrey Benkoe)