US STOCKS-S&P futures edge up as earnings offset rally concern

* Investors fret that market's rally is waning

* Consumer confidence, Case-Shiller data on tap

* Futures: S&P up 0.5 pt, Dow up 9 pts, Nasdaq off 3.5 pts

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By Leah Schnurr

NEW YORK, Oct 27 (Reuters) - S&P 500 index futures edged higher on Tuesday following a two-day selloff as better-than-expected earnings offset worries that the market's seven-month rally was reaching its end.

Energy shares could get support after BP Plc beat third-quarter earnings forecasts by a big margin as its cost-cutting program proved more successful than expected, prompting the oil major to increase its target for savings for the year. For details, see [ID:nLQ683027]

Exxon Mobil Corp gained 0.7 percent to $73.75 in premarket trades.

But the Nasdaq could see pressure as Baidu Inc slumped 17.7 percent to $356.12 before the bell after China's top search engine said a rocky introduction for its new system to sell search-based advertising will hit its business into the first quarter of next year. [ID:nSHA283787]

Investors fretted that the market might be hitting a plateau. The S&P 500 is now up 57.7 percent from the 12-year closing low of March 9, having slipped from its recovery peak when it was up 62.3 percent from that low.

"It's showing the market has clearly gotten tired," said Peter Boockvar, equity strategist at Miller Tabak & Co in New York. "A correction has begun. It's just a matter of to what degree."

So far, dips have been shallow and short-lived as investors use them as opportunities to get into the market.

S&P 500 futures rose 0.5 of a point 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 gained 9 points, while Nasdaq futures were off 3.5 points.

Stocks fell for a second straight session on Monday as investors ditched home builders and financials on fears lawmakers may let a federal home buyer tax credit expire, while commodity shares succumbed to pressure from the higher U.S. dollar.

Without the home buyer credit, investors worry that the struggling housing market might lose a crucial incentive that has spurred hopes of stabilization in recent months.

On the macro front, investors awaited U.S. consumer confidence data for October, due at 10:00 a.m. (1400 GMT) The index is expected to be flat with September's level at 53.1, according to a Reuters survey of economists. Also due are Case-Shiller home price indexes for August at 9:00 a.m. (1300 GMT).

Healthcare stocks could be pressured after Democratic U.S. Senate leader Harry Reid said on Monday the Senate's healthcare overhaul will include a government-run insurance plan that lets states opt out. [ID:nN26208629] (Editing by Padraic Cassidy)