* Jan jobs growth below forecasts, but Dec revised higher
* Exxon and Chevron both beat profit forecasts
* Merck shares fall in premarket on lower outlook
* Indexes up: Dow 116 pts, S&P 10.7 pts, Nasdaq 21.5 pts
By Ryan Vlastelica
NEW YORK, Feb 1 (Reuters) - U.S. stock index futures were poised to open higher Friday as a slight disappointment in the January payroll report was offset by a strong upward revision for jobs in December.
Employment grew modestly in January, with 157,000 added in the month, slightly below expectations for 160,000. Still, the December report was revised upward to 196,000 from 155,000, supporting views the U.S. economic recovery remained on track despite a surprise contraction in fourth-quarter gross domestic product.
"Nice revision upward, and this month came in right at the sweet spot where job growth is picking up, but not at the point where the Fed's quantitative easing program is threatened," said Mark Luschini, chief investment strategist at Janney Montgomery Scott in Philadelphia.
The market may be vulnerable to a pullback at recent levels, and may see the S&P 500 coming off its best monthly performance since October 2011. However, declines may be limited, with investors having bought on dips over the past four weeks; the biggest daily drop on the S&P so far this year was just 0.39 percent.
"The market may be at something of a top here, but we are rising on improved economic fundamentals so the rally has been rational," said Luschini, who helps oversee $55 billion in assets.
Corporate earnings were also a focus for investors, with a trio of Dow components reporting profits that beat expectations.
Exxon Mobil Corp rose 0.7 percent to $90.60 in premarket trading after its results, and drugmaker Merck & Co fell 2.9 percent to $42. While Merck's profit was ahead of forecasts it gave a cautious outlook on 2013.
Chevron Corp rose 3 cents to $115.18 before the bell as its profit beat expectations.
S&P 500 futures rose 10.7 points and were above 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 added 116 points and Nasdaq 100 futures rose 21.5 points.
The S&P advanced 5.1 percent in January, with gains driven by a sturdy start to the earnings season and a compromise in Washington that postponed the impact of a "fiscal cliff" of automatic spending cuts and tax hikes that were due to take effect early this year.
Of the 231 companies in the S&P 500 reporting earnings so far, 69.3 percent have exceeded expectations, according to Thomson Reuters data through Thursday morning. That is a higher proportion than over the past four quarters and above average since 1994.
Overall, S&P 500 fourth-quarter earnings rose 3.7 percent, according to the data, above a 1.9 percent forecast at the start of the earnings season but well below a 9.9 percent profit growth forecast on Oct. 1.
Other data due Friday include consumer sentiment, U.S. manufacturing, construction spending and car sales. January sentiment is seen edging slightly higher in the month while construction spending rises 0.6 percent in December.
U.S. stocks closed lower on Thursday amid investor caution ahead of the payroll report.