NEW YORK (Reuters) - Stock futures dropped on Thursday as a...

NEW YORK (Reuters) - Stock futures dropped on Thursday as a profit warning from Capital One Financial Corp (COF.N: Quote, Profile, Research), a credit card issuer and banking company, fueled concerns about the impact of the credit crisis and fallout from the housing slump.

The outlook from Capital One tempered optimism from a report about possible capital injections for Citigroup Inc (C.N: Quote, Profile, Research) and Merrill Lynch & Co Inc (MER.N: Quote, Profile, Research).

Capital One shares were down more than 2 percent in Europe in light volume, but Citigroup shares shot up 3.3 percent and those of Merrill gained 6 percent.

The Wall Street Journal reported that Citigroup and Merrill were in discussions to get more capital from investors, primarily foreign governments.

But with Capital One again indicating no let-up in the credit woes and fallout from the housing slump, investors appeared set to tread cautiously.

"Capital One is what's pushing the market down. It looks like we're going to have a dismal opening," said Paul Mendelsohn, chief investment strategist at Windham Financial Services in Charlotte, Vermont.

"This shows that the consumer isn't just in trouble with their houses, but they are getting into trouble with their credit cards as well."

S&P 500 futures fell 4.6 points and were below fair value, a mathematical formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract.

Dow Jones industrial average futures were down 27 points. Nasdaq 100 futures were off 4 points.

Capital One said it expects full-year earnings of around $3.97 per share, below its previous expectation of "about $5.00 per share," blaming higher provisions for bad debts and additional legal reserves.

Investors will also look for signs of what the Federal Reserve might do at its next meeting when Chairman Ben Bernanke speaks on markets and the economy at 1 p.m. EST. Fed policy-makers will meet on January 29-30.

Major U.S. retailers are also due to post December same-store sales which will be scrutinized for clues about how the consumer is faring as fears of a recession swell.

The Wall Street Journal said Citigroup could get as much as $10 billion, likely all from foreign governments, while Merrill is expected to get $3 billion to $4 billion, much of it from a Middle Eastern government investment fund.

U.S. stocks rose on Wednesday and the Nasdaq broke an eight-day string of losses as investors bought stocks in health care and other defensive sectors seen as resistant to a slowdown.