NEW YORK (CNN/Money) - A gauge of American consumer confidence could move U.S. stocks Tuesday, a day after the Nasdaq composite index once again gave up its gains for the year.

Due after the market opens, the Conference Board's consumer confidence index is expected to have slipped to 77 in February from 79 the preceding month, according to the consensus forecast of economists surveyed by Briefing.com.

February was a month of rising oil prices and falling stock prices that came as the U.S. amassed troops in the Persian Gulf for a possible war with Iraq.

Earlier this month, the University of Michigan said its consumer sentiment index fell to the lowest level in more than nine years in February. A poll Monday showed that 35 percent of investors said they are optimistic about the prospects of economic growth over the next 12 months, a record low and down from 42 percent in January.

While consumer spending fuels most of the economy, uncertainty about Iraq has weighed on business confidence, causing many corporate executives to delay spending and hiring. But some economists say that even after Iraq, the drag from the burst investment bubble of the late 1990s will continue.

In after-hours trading Monday, H&R Block (HRB: Research, Estimates) jumped 80 cents to $38. The No. 1 U.S. tax preparer reported sharply higher earnings, helped by growth in its mortgage business.

But Overstock.com (OSTK: Research, Estimates) tumbled $2.91 to $15.20 in late trading. The company's chief executive, Patrick Byrne, said the two analysts who cover the online retailer have issued first- quarter profit estimates that are too aggressive. According to First Call, the two analysts see the company losing 1 cent a share or earning 1 cent a share in the first quarter ending in March.

In other after-hours trading, Ligand Pharmaceuticals (LGND: Research, Estimates) rose 10 cents to $4.90. The company said it will co-promote its treatment for chronic, moderate-to-severe pain, called Avinza, with the Dutch drugmaker Akzo Nobel (AKZOY: Research, Estimates).

In other economic data Tuesday, existing homes sales are expected to have slipped to an annual rate of 5.80 million in January from 5.86 million the prior month. Last year saw a record 5.56 million existing homes sold, the strongest year since the National Association of Realtors started tracking the figures in 1968.

Two components of the Dow Jones industrial average release quarterly financial data Tuesday.

Home Depot (HD: Research, Estimates) reports results before the market opens, and numbers from Hewlett-Packard (HWP: Research, Estimates) are due after the close.

Amgen (AMGN: Research, Estimates) and Adolph Coors (RKY: Research, Estimates) are meeting with analysts Tuesday.

U.S. stocks fell Monday, pushing the Nasdaq 1 percent lower. The Dow's 2003 losses widened to 5.9 percent.  

-- Reuters contributed to this report