* China stimulus hopes boost optimism
* Spanish bank worry continues
* Facebook may be in talks to buy Opera
* Futures up: Dow 104 pts, S&P 9.2 pts, Nasdaq 14.5 pts
By Chuck Mikolajczak
NEW YORK, May 29 (Reuters) - U.S. stock index futures rose on Tuesday, indicating a rally in equities may continue after their first weekly gain since April, on hopes China may unleash more spending measures and Greek election polls pointed to support for conservative parties.
* The official Shanghai Securities News reported on Tuesday, citing unidentified sources, that China’s biggest banks appeared to have accelerated lending toward the end of this month as Beijing starts to fast-track its approval of infrastructure investments in an effort to stem sagging growth.
* Investors were also encouraged by weekend polls in Greece that showed the conservative New Democracy party, which backs the country’s international bailout, has a lead over the leftist SYRIZA party, which opposes it ahead of a June 17 election. In Ireland, voters appear poised to reluctantly approve Europe’s new fiscal treaty.
* But concern about Spain’s banking system continued to weigh on investors, causing the FTSEurofirst 300 to pull back from early gains as yields on 10-year Spanish bonds remained just under 6.5 percent. Many investors view the 7-percent mark as unsustainable, which could trigger the need for a bailout.
* U.S. data expected on Tuesday includes the S&P/Case Shiller Home Price Index for March at 9:00 a.m. (1300 GMT). Economists expect the 20-city seasonally adjusted index to rise 0.2 percent month over month, the same increase as in February.
* May consumer confidence numbers from the Conference Board, an industry group, are due at 10 a.m. (1400 GMT). Economists expect a rise to 70.0 from 69.2 in April.
* S&P 500 futures rose 9.2 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 gained 104 points, and Nasdaq 100 futures added 14.5 points.
* Opera Software shares soared more than 20 percent in Oslo on Tuesday on talk Facebook Inc was in discussion to buy the firm, while analysts said competition from Google Inc and others could push the price tag of any deal above $1 billion.
* JPMorgan Chase & Co has sold an estimated $25 billion of profitable securities in an effort to prop up earnings after suffering trading losses tied to the bank’s now-infamous “London Whale,” derivatives losses at its London office, compounding the cost of those trades.
* Asian shares advanced over speculation about China’s possible push to avoid a slowdown.