S&P 500 futures were up 0.8 points by 0938 GMT, having reversed earlier losses after challenger Mitt Romney conceded defeat. Under Obama, the Federal Reserve is expected to continue with its 'quantitative easing' stimulus programme, lending continued support to financial markets and the economy.

Nasdaq 100 futures rose 3.8 points, though Dow Jones industrial average futures were down 9 points in volatile European morning trade.

Investors remained skeptical about the scale and durability of equity gains, with the focus now likely to turn to the "fiscal cliff" of some $600 billion in spending cuts and tax increases that are due to kick in next year and could derail the U.S. economic recovery.

"We have seen a euphoric rally over the Obama victory ... It is down to the fact that there will be less pressure on the Fed to change policy," said Stewart Richard, chief investment officer at London-based RMG, which holds a long position in U.S. equities partially hedged through implied volatility.

"But the upside in the very short term is limited because of the fiscal cliff issue. We don't intend to chase this rally."

U.S. futures also signaled to a more cautious mood than the European cash equity markets, which climbed to two-week highs. .EU

Although markets had expected an Obama victory, most traders and investors had backed Romney, who was seen as more pro-business and had raised more money on Wall Street.

Coal and defense shares had been seen as potential beneficiaries in case of a Romney win, although overall investors agreed that uncertainty would have been the worst outcome.

"What appears to be a decisive victory by President Obama in the U.S. presidential election will at least remove concerns of a prolonged period of uncertainty following what could have been a closely contested result," analysts at Credit Agricole CIB said in a note.

"Obama will now face the colossal task of resolving the looming fiscal cliff. Other indicators are not particularly rosy, with the Baltic Dry Index extending its declines overnight, perhaps indicating renewed growth concerns while the East coast of the U.S. is bracing for another storm, hot on the heels of Sandy."

Aside from digesting the election results, investors will also stay focused on third-quarter earnings, which have so far seen 68 percent of U.S. blue chips beat or meet earnings expectations, according to Thomson Reuters Starmine.

Shares in Rupert Murdoch's News Corp (NWSA.O) rose after the bell on Tuesday when the group reported forecast-beating profits.

Companies reporting on Wednesday include Kraft Foods Group (KRFT.O), Macy's (M.N) and Time Warner (TWX.N).

The S&P 500 closed 0.8 percent higher at 1,428.39 points on Tuesday .SPX.

(Additional reporting by Rodrigo Campos in New York; Editing by Susan Fenton)

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