SEATTLE - Leaders of this famously green city last year passed the nation's first grocery-bag fee, and other cities around the nation quickly followed.

But the plastics industry has been fighting back, bringing lawsuits, aggressively lobbying lawmakers, and bankrolling a referendum in Seattle that aims to overturn the 20-cent charge. The measure goes before voters Tuesday, and polls show marginal support after the industry spent $1.4 million, outspending supporters of the bag fee by a ratio of about 15-1.

If the bag fee fails in an eco-conscious city such as Seattle, observers say, it will be a tough sell elsewhere.

"This amount of money is about bullying public officials," said Rob Gala, a spokesman for Seattle Green Bag campaign, which has raised about $93,000 to back the fee. "They're trying to send a message to elected officials across the country who are thinking about similar measures."

In California, bag manufacturers successfully sued Oakland and Manhattan Beach after those cities banned plastic bags. The bag-makers complained that officials did not prepare a report detailing the environmental impact, such as the increased use of paper sacks.

"We've seen lobbying and blatant attempts to intimidate cities," said David Lewis, executive director of Save the Bay in Oakland. He likened the efforts to the tobacco industry's campaign to fight smoking bans.

The lawsuits are working, said Stephen Joseph, a lawyer representing SaveThePlasticBag.com, which has sued Palo Alto, Los Angeles County, and Manhattan Beach in the last year. The group includes California-based Crown Poly Inc., Command Packaging, and Elkay Plastics Co.

While Manhattan Beach is appealing a court ruling in favor of the industry, city attorney Bob Wadden said he had heard from other cities that fear being sued if they pursue a similar ban.

Several states, including Colorado, Texas, and Virginia, debated bag bans or fees this year, but no statewide ban or fee has been enacted. Washington, D.C., passed a 5-cent fee on paper or plastic bags, and the Outer Banks region in North Carolina banned plastic bags this year. But New York City dropped a proposed 5-cent bag fee, and in June, Philadelphia's City Council rejected a plastic-bag ban.

In Seattle, the Progressive Bag Affiliates, an arm of the Virginia-based American Chemistry Council, has given the bulk of money to defeat the bag fee.

"Seattle residents have a right to know the facts about new taxes that will impact them, and public outreach is expensive," the council said in a statement explaining its contributions.

Seattle's fee is unusual in that it also covers paper bags, which the city determined are worse for the environment than plastic. Targeting only plastic bags, the city said, would push people to use paper, resulting in greater greenhouse gases.

The industry has latched on to that point in fighting ordinances elsewhere. Most measures have targeted only plastic bags, nearly 88 billion of which were sold in the United States in 2003, according to the latest figures from the International Trade Commission.

Plastic-bag supporters say paper bags are more costly, take more energy and water to make, and release methane - a greenhouse gas - when they decompose. But plastic bags are recycled at a lower rate than paper sacks, according to the Environmental Protection Agency, and they take hundreds of years to break down in landfills.