ALBANY – Senate Republicans are considering legislation that would force hundreds of businesses, particularly retailers like Wal-Mart, to pay for health insurance for their employees.

The bill, which is being pushed by the politically influential Working Families Party and is expected to be introduced by Democrats in the Assembly and Republicans in the state Senate next week, would require companies with 100 or more employees to cover their health insurance costs at a rate of $3 an hour. Manufacturing and agricultural firms would be exempted, and the bill would not cover employees who hold executive, professional, or administrative positions.

The Republican majority leader of the Senate, Joseph Bruno, said yesterday that he would “examine” the legislation, and agreed with a primary contention of the bill’s sponsors that it is unfair for the state government to shoulder the burden of insurance costs of New Yorkers working for large companies like Wal-Mart. Though Wal-Mart offers its employees health plans, many of its employees in New York are eligible for Medicaid and opt for the government program, which offers more benefits.

Some political observers here say Mr. Bruno’s stance on the bill is in part a reflection of the growing influence of the Working Families Party in New York politics and particularly on the Senate, where Republicans are concerned about protecting a tenuous four seat majority. Candidates for public office in New York can run on any number of ballot lines, and the competition for third-party endorsements, which frequently push candidates over the edge of victory, tends to be fierce.

The party, which was founded in 1998 and is affiliated with more than 60 labor unions and community groups, endorsed 10 Republican senators in 2004 and takes credit for providing the extraordinarily slim margin of victory to Nick Spano, a Republican who is the primary sponsor of the Senate bill. Mr. Spano, whose Westchester district is heavily Democratic, won by a margin of less than one percentage point in 2004, receiving more than 1,700 votes on the Working Families Party line.

“What we’re saying is – and we’re going to examine it and all the ramifications of it as to whether it is counterproductive in terms of business. We’re going to look at it very closely,” Mr. Bruno said yesterday at a press conference where he was asked about the bill. “Because when some of the so-called big box stores say to their employees, here is an application to go to apply to Family Health Plus or Healthy New York and get your insurance, that’s a taxpayer expense, while the place next door is providing health insurance as part of their overhead. It’s inequitable. It’s unfair. That is what has prompted this legislation. And we’re going to look at it.”

Governor Pataki will review the bill and will not comment otherwise on it, a spokesman said.

Supporters of the legislation say it would level the playing field between businesses in the state that provide health coverage to their employees and those that do not, and they also argue that it would shift more of the burden of paying for health care onto the business and away from the government.

New York is one of more than a dozen states considering such legislation. The bill resembles legislation that Maryland passed in January requiring businesses with 10,000 or more employees to spend at least 8% of their revenue on health benefits. While the Maryland law is aimed squarely at Wal-Mart, one of the only businesses in the state covered by it, New York State lawmakers are proposing legislation that is much wider in scope. The New York City Council recently passed similar legislation, overriding Mayor Bloomberg’s veto, although there are no Wal-Marts in New York City.

Mr. Spano, who was among the 51 senators to override the governor’s veto on a minimum wage increase in 2004, said in an interview with The New York Sun that his bill would “improve the dignity of workers.” He denied that his support for the bill was politically motivated, saying he was “performing my job as senator no differently than I’ve done before.”

The bill has quickly met with fierce resistance from fiscal conservatives who say the added expense would force companies to fire employees and would drive more businesses out of New York, whose sales, personal income, and business taxes are significantly higher than the nation’s average. A recent study by the Tax Foundation found that New York has the most hostile business tax climate in the nation.

Opponents of the bill say one of the reasons why government is picking up so much of the costs is because of expanded Medicaid eligibility requirements. They also say companies like Wal-Mart help to reduce government expenses by hiring people who were receiving welfare support.

Matthew Maguire, a spokesman for the Business Council of New York State, said the legislation would “drive costs up and drive employers out.”

It’s not clear how many businesses would be affected by the bill but “it could be thousands,” said Tarren Bragdon, a health policy analyst at the Empire Center for New York State Policy, a division of the Manhattan Institute think tank. “The target is probably retail businesses, but the bill, would include businesses beyond retail, including other aspects of the service industry such as hospitality.”

A draft version characterizes it as an effort to “protect the taxpayers,” saying that government “must ensure that the state’s large employers do their fair share to pay for their employees’ health care costs.”

A spokesman for the Working Families Party said the bill does not include manufacturing and agricultural firms because they face international competition and would be put at a greater disadvantage. The $3-per-hour figure is an average of what the party believes is the cost of providing health insurance for an employee.