SPRINGFIELD, MO. — Wal-Mart Stores Inc. announced more affordable healthcare for some of its workers yesterday in the latest shot in a battle with critics for the hearts of consumers. The move by the world's largest retailer comes as the crucial holiday sales season approaches.

Analysts say Wal-Mart needs to add about $250 million a day in sales during the holiday season to meet earnings targets and cannot afford to lose ground to an increasingly united front of opponents who want consumers to shun the discounter until it changes its ways.

"Consumers increasingly have a conscience and are increasingly shifting to competitors," said Burt Flickinger, managing director of Strategic Marketing.

"It is critical for Wal-Mart to start doing a billion dollars a day in sales starting on Black Friday, the day after Thanksgiving, which is the big 30-day push for Christmas and year-end sales," Flickinger said. He said daily sales are now about $750 million.

Pressure on Wal-Mart has mounted as groups from unions to the Sierra Club to the National Organization of Women have linked up, creating two new campaign organizations this year, Wake-Up Wal-Mart and Wal-Mart Watch.

"Where there is pressure there is change, universally," said Richard Hastings, senior retail analyst at Bernard Sands in New York.

Wal-Mart says it is not responding to outside critics but rather to demand from its employees, or associates in Wal-Mart parlance, by launching a plan to lower health insurance premiums, allowing some to buy coverage for as little as $11 per month.

Wal-Mart spokesman Dan Fogleman would not say how much the plan would cost the Bentonville, Ark.-based company, which has 1.2 million domestic employees. The plan is to go into effect in 2006.

The move comes as Wal-Mart has been under increasing criticism for not offering health coverage to enough workers and for its high costs to employees for the insurance, which include high deductibles. Fewer than half of Wal-Mart's employees are covered by the company healthcare plan, compared to 80 percent at rival Costco Wholesale Corp.

Wal-Mart's critics have said some company workers have had to rely on government-funded programs to pay for healthcare, an issue that has spurred federal legislation aimed at pressuring the retailer to be more generous.

Compared to Wal-Mart's current plan, monthly premiums under the new plan would require workers to pay between 40 percent and 60 percent less. The plan would have a $1,000 deductible but would allow individuals three doctor visits before having to pay the deductible, according to The New York Times, which first reported on the plan.

The $11 monthly premium won't be widely available. The plan would have most individuals pay about $25 per month, and $65 for a family. A single parent would pay $37 per month. The plan has a $25,000 cap for a worker's first year with the insurance.

It is the latest move in a series of changes after Wal-Mart earlier this year took out full-page ads in national newspapers to defend itself as good for the economy, employees and consumers.

Last week, Wal-Mart Chief Executive Lee Scott said the company, which imported $18 billion in goods from China last year, would push overseas manufacturers to raise environmental and social standards. Critics have accused it of selling cheap goods from sweatshop factories.

Wal-Mart also last week announced it would invest $25 million to establish a private equity fund to back women and minority-owned business enterprises. The company faces a class-action lawsuit on behalf of up to 1.6 million current and former female employees alleging it discriminates against women in pay and promotions.

Wal-Mart's opponents have so far largely dismissed the initiatives as publicity stunts.

Wake-Up Wal-Mart, supported by the United Food and Commercial Workers Union, said the new health plan was just a repackaging of Wal-Mart's existing coverage.

"Wal-Mart fails to address the key reasons more than half of its employees aren't covered under their healthcare plan — ridiculously high deductible costs and overly strict eligibility requirements," Wake-Up Wal-Mart campaign director Paul Blank said in a news release.

Wal-Mart Watch said the moves so far may be good but do not address a central allegation, that the company pays substandard wages.

"That is a burden not just on people struggling to make ends meet, it becomes a burden on taxpayers, it becomes a burden on communities, and Wal-Mart sits back and counts their billions," Wal-Mart Watch spokeswoman Tracy Sefl said.

Wal-Mart shares rose 49 cents, or 1.1 percent, to close at $46.21 on the New York Stock Exchange. It shares have traded in a 52-week range of $42.31 to $57.89.