Stocks rose on Wednesday, lifted by slightly better-than-expected jobs and services data, as well as an upbeat outlook from Priceline.com.

Priceline.com Inc

soared 23.5 percent to $284.80 after several brokers raised price estimates for the online travel agency's stock, based on its stronger-than-expected quarterly results.

Priceline was the top performer in both the S&P 500 <.SPX> and the Nasdaq 100 <.NDX>.

The services sector grew slightly more than expected in July, according to the Institute for Supply Management index. A separate report from payroll-processing company ADP showed that in July, private employers added more jobs than forecast.

Still, the picture of the economy was still listless and investors remained cautious ahead of the U.S. government's key monthly jobs report on Friday.

ADP certainly gave a little glimmer of hope the jobs number on Friday might be more positive than anticipated, said Kim Caughey, senior equity research analyst at Fort Pitt Capital Group in Pittsburgh.

But she said the high unemployment rate keeps consumers jittery and retailers' margins are probably being hit as they try to drive sales.

The high proportion of the economy that is consumer oriented gives investors pause, she said.

Friday's government report on jobs is expected to show a drop of 65,000 in July as Census jobs evaporated.

The Dow Jones industrial average <.DJI> gained 47.42 points, or 0.45 percent, to 10,683.80. The Standard & Poor's 500 <.SPX> added 5.14 points, or 0.46 percent, to 1,125.60. The Nasdaq Composite <.IXIC> rose 16.44 points, or 0.72 percent, to 2,299.95.

With 80 percent of the S&P 500 companies having reported quarterly results, estimated and reported earnings growth stands at 37.3 percent for the previous quarter, up from an estimate of 27.4 percent a month ago, according to Thomson Reuters Proprietary Research.

Another boost to the Nasdaq came from Dendreon Corp , up 15.1 percent at $38.90 on details of the launch of the company's new prostate cancer vaccine and news that it was piling up favorable reimbursement notices from health plans.

Microsoft Corp weighed on the downside, losing 1.8 percent to $25.68 after Global Equities Research downgraded the stock to equal weight from overweight.

(Editing by Jan Paschal)